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diff --git a/src/assets/viz/1/goog/i18n/bidi.js b/src/assets/viz/1/goog/i18n/bidi.js
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+// Copyright 2007 The Closure Library Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS-IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @fileoverview Utility functions for supporting Bidi issues.
+ */
+
+
+/**
+ * Namespace for bidi supporting functions.
+ */
+goog.provide('goog.i18n.bidi');
+goog.provide('goog.i18n.bidi.Dir');
+goog.provide('goog.i18n.bidi.DirectionalString');
+goog.provide('goog.i18n.bidi.Format');
+
+
+/**
+ * @define {boolean} FORCE_RTL forces the {@link goog.i18n.bidi.IS_RTL} constant
+ * to say that the current locale is a RTL locale.  This should only be used
+ * if you want to override the default behavior for deciding whether the
+ * current locale is RTL or not.
+ *
+ * {@see goog.i18n.bidi.IS_RTL}
+ */
+goog.define('goog.i18n.bidi.FORCE_RTL', false);
+
+
+/**
+ * Constant that defines whether or not the current locale is a RTL locale.
+ * If {@link goog.i18n.bidi.FORCE_RTL} is not true, this constant will default
+ * to check that {@link goog.LOCALE} is one of a few major RTL locales.
+ *
+ * <p>This is designed to be a maximally efficient compile-time constant. For
+ * example, for the default goog.LOCALE, compiling
+ * "if (goog.i18n.bidi.IS_RTL) alert('rtl') else {}" should produce no code. It
+ * is this design consideration that limits the implementation to only
+ * supporting a few major RTL locales, as opposed to the broader repertoire of
+ * something like goog.i18n.bidi.isRtlLanguage.
+ *
+ * <p>Since this constant refers to the directionality of the locale, it is up
+ * to the caller to determine if this constant should also be used for the
+ * direction of the UI.
+ *
+ * {@see goog.LOCALE}
+ *
+ * @type {boolean}
+ *
+ * TODO(user): write a test that checks that this is a compile-time constant.
+ */
+goog.i18n.bidi.IS_RTL = goog.i18n.bidi.FORCE_RTL ||
+    ((goog.LOCALE.substring(0, 2).toLowerCase() == 'ar' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'fa' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'he' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'iw' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'ps' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'sd' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'ug' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'ur' ||
+      goog.LOCALE.substring(0, 2).toLowerCase() == 'yi') &&
+     (goog.LOCALE.length == 2 || goog.LOCALE.substring(2, 3) == '-' ||
+      goog.LOCALE.substring(2, 3) == '_')) ||
+    (goog.LOCALE.length >= 3 &&
+     goog.LOCALE.substring(0, 3).toLowerCase() == 'ckb' &&
+     (goog.LOCALE.length == 3 || goog.LOCALE.substring(3, 4) == '-' ||
+      goog.LOCALE.substring(3, 4) == '_'));
+
+
+/**
+ * Unicode formatting characters and directionality string constants.
+ * @enum {string}
+ */
+goog.i18n.bidi.Format = {
+  /** Unicode "Left-To-Right Embedding" (LRE) character. */
+  LRE: '\u202A',
+  /** Unicode "Right-To-Left Embedding" (RLE) character. */
+  RLE: '\u202B',
+  /** Unicode "Pop Directional Formatting" (PDF) character. */
+  PDF: '\u202C',
+  /** Unicode "Left-To-Right Mark" (LRM) character. */
+  LRM: '\u200E',
+  /** Unicode "Right-To-Left Mark" (RLM) character. */
+  RLM: '\u200F'
+};
+
+
+/**
+ * Directionality enum.
+ * @enum {number}
+ */
+goog.i18n.bidi.Dir = {
+  /**
+   * Left-to-right.
+   */
+  LTR: 1,
+
+  /**
+   * Right-to-left.
+   */
+  RTL: -1,
+
+  /**
+   * Neither left-to-right nor right-to-left.
+   */
+  NEUTRAL: 0
+};
+
+
+/**
+ * 'right' string constant.
+ * @type {string}
+ */
+goog.i18n.bidi.RIGHT = 'right';
+
+
+/**
+ * 'left' string constant.
+ * @type {string}
+ */
+goog.i18n.bidi.LEFT = 'left';
+
+
+/**
+ * 'left' if locale is RTL, 'right' if not.
+ * @type {string}
+ */
+goog.i18n.bidi.I18N_RIGHT =
+    goog.i18n.bidi.IS_RTL ? goog.i18n.bidi.LEFT : goog.i18n.bidi.RIGHT;
+
+
+/**
+ * 'right' if locale is RTL, 'left' if not.
+ * @type {string}
+ */
+goog.i18n.bidi.I18N_LEFT =
+    goog.i18n.bidi.IS_RTL ? goog.i18n.bidi.RIGHT : goog.i18n.bidi.LEFT;
+
+
+/**
+ * Convert a directionality given in various formats to a goog.i18n.bidi.Dir
+ * constant. Useful for interaction with different standards of directionality
+ * representation.
+ *
+ * @param {goog.i18n.bidi.Dir|number|boolean|null} givenDir Directionality given
+ *     in one of the following formats:
+ *     1. A goog.i18n.bidi.Dir constant.
+ *     2. A number (positive = LTR, negative = RTL, 0 = neutral).
+ *     3. A boolean (true = RTL, false = LTR).
+ *     4. A null for unknown directionality.
+ * @param {boolean=} opt_noNeutral Whether a givenDir of zero or
+ *     goog.i18n.bidi.Dir.NEUTRAL should be treated as null, i.e. unknown, in
+ *     order to preserve legacy behavior.
+ * @return {?goog.i18n.bidi.Dir} A goog.i18n.bidi.Dir constant matching the
+ *     given directionality. If given null, returns null (i.e. unknown).
+ */
+goog.i18n.bidi.toDir = function(givenDir, opt_noNeutral) {
+  if (typeof givenDir == 'number') {
+    // This includes the non-null goog.i18n.bidi.Dir case.
+    return givenDir > 0 ? goog.i18n.bidi.Dir.LTR : givenDir < 0 ?
+                          goog.i18n.bidi.Dir.RTL :
+                          opt_noNeutral ? null : goog.i18n.bidi.Dir.NEUTRAL;
+  } else if (givenDir == null) {
+    return null;
+  } else {
+    // Must be typeof givenDir == 'boolean'.
+    return givenDir ? goog.i18n.bidi.Dir.RTL : goog.i18n.bidi.Dir.LTR;
+  }
+};
+
+
+/**
+ * A practical pattern to identify strong LTR characters. This pattern is not
+ * theoretically correct according to the Unicode standard. It is simplified for
+ * performance and small code size.
+ * @type {string}
+ * @private
+ */
+goog.i18n.bidi.ltrChars_ =
+    'A-Za-z\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u02B8\u0300-\u0590\u0800-\u1FFF' +
+    '\u200E\u2C00-\uFB1C\uFE00-\uFE6F\uFEFD-\uFFFF';
+
+
+/**
+ * A practical pattern to identify strong RTL character. This pattern is not
+ * theoretically correct according to the Unicode standard. It is simplified
+ * for performance and small code size.
+ * @type {string}
+ * @private
+ */
+goog.i18n.bidi.rtlChars_ =
+    '\u0591-\u06EF\u06FA-\u07FF\u200F\uFB1D-\uFDFF\uFE70-\uFEFC';
+
+
+/**
+ * Simplified regular expression for an HTML tag (opening or closing) or an HTML
+ * escape. We might want to skip over such expressions when estimating the text
+ * directionality.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.htmlSkipReg_ = /<[^>]*>|&[^;]+;/g;
+
+
+/**
+ * Returns the input text with spaces instead of HTML tags or HTML escapes, if
+ * opt_isStripNeeded is true. Else returns the input as is.
+ * Useful for text directionality estimation.
+ * Note: the function should not be used in other contexts; it is not 100%
+ * correct, but rather a good-enough implementation for directionality
+ * estimation purposes.
+ * @param {string} str The given string.
+ * @param {boolean=} opt_isStripNeeded Whether to perform the stripping.
+ *     Default: false (to retain consistency with calling functions).
+ * @return {string} The given string cleaned of HTML tags / escapes.
+ * @private
+ */
+goog.i18n.bidi.stripHtmlIfNeeded_ = function(str, opt_isStripNeeded) {
+  return opt_isStripNeeded ? str.replace(goog.i18n.bidi.htmlSkipReg_, '') : str;
+};
+
+
+/**
+ * Regular expression to check for RTL characters.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rtlCharReg_ = new RegExp('[' + goog.i18n.bidi.rtlChars_ + ']');
+
+
+/**
+ * Regular expression to check for LTR characters.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.ltrCharReg_ = new RegExp('[' + goog.i18n.bidi.ltrChars_ + ']');
+
+
+/**
+ * Test whether the given string has any RTL characters in it.
+ * @param {string} str The given string that need to be tested.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether the string contains RTL characters.
+ */
+goog.i18n.bidi.hasAnyRtl = function(str, opt_isHtml) {
+  return goog.i18n.bidi.rtlCharReg_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Test whether the given string has any RTL characters in it.
+ * @param {string} str The given string that need to be tested.
+ * @return {boolean} Whether the string contains RTL characters.
+ * @deprecated Use hasAnyRtl.
+ */
+goog.i18n.bidi.hasRtlChar = goog.i18n.bidi.hasAnyRtl;
+
+
+/**
+ * Test whether the given string has any LTR characters in it.
+ * @param {string} str The given string that need to be tested.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether the string contains LTR characters.
+ */
+goog.i18n.bidi.hasAnyLtr = function(str, opt_isHtml) {
+  return goog.i18n.bidi.ltrCharReg_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Regular expression pattern to check if the first character in the string
+ * is LTR.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.ltrRe_ = new RegExp('^[' + goog.i18n.bidi.ltrChars_ + ']');
+
+
+/**
+ * Regular expression pattern to check if the first character in the string
+ * is RTL.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rtlRe_ = new RegExp('^[' + goog.i18n.bidi.rtlChars_ + ']');
+
+
+/**
+ * Check if the first character in the string is RTL or not.
+ * @param {string} str The given string that need to be tested.
+ * @return {boolean} Whether the first character in str is an RTL char.
+ */
+goog.i18n.bidi.isRtlChar = function(str) {
+  return goog.i18n.bidi.rtlRe_.test(str);
+};
+
+
+/**
+ * Check if the first character in the string is LTR or not.
+ * @param {string} str The given string that need to be tested.
+ * @return {boolean} Whether the first character in str is an LTR char.
+ */
+goog.i18n.bidi.isLtrChar = function(str) {
+  return goog.i18n.bidi.ltrRe_.test(str);
+};
+
+
+/**
+ * Check if the first character in the string is neutral or not.
+ * @param {string} str The given string that need to be tested.
+ * @return {boolean} Whether the first character in str is a neutral char.
+ */
+goog.i18n.bidi.isNeutralChar = function(str) {
+  return !goog.i18n.bidi.isLtrChar(str) && !goog.i18n.bidi.isRtlChar(str);
+};
+
+
+/**
+ * Regular expressions to check if a piece of text is of LTR directionality
+ * on first character with strong directionality.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.ltrDirCheckRe_ = new RegExp(
+    '^[^' + goog.i18n.bidi.rtlChars_ + ']*[' + goog.i18n.bidi.ltrChars_ + ']');
+
+
+/**
+ * Regular expressions to check if a piece of text is of RTL directionality
+ * on first character with strong directionality.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rtlDirCheckRe_ = new RegExp(
+    '^[^' + goog.i18n.bidi.ltrChars_ + ']*[' + goog.i18n.bidi.rtlChars_ + ']');
+
+
+/**
+ * Check whether the first strongly directional character (if any) is RTL.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether RTL directionality is detected using the first
+ *     strongly-directional character method.
+ */
+goog.i18n.bidi.startsWithRtl = function(str, opt_isHtml) {
+  return goog.i18n.bidi.rtlDirCheckRe_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Check whether the first strongly directional character (if any) is RTL.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether RTL directionality is detected using the first
+ *     strongly-directional character method.
+ * @deprecated Use startsWithRtl.
+ */
+goog.i18n.bidi.isRtlText = goog.i18n.bidi.startsWithRtl;
+
+
+/**
+ * Check whether the first strongly directional character (if any) is LTR.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether LTR directionality is detected using the first
+ *     strongly-directional character method.
+ */
+goog.i18n.bidi.startsWithLtr = function(str, opt_isHtml) {
+  return goog.i18n.bidi.ltrDirCheckRe_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Check whether the first strongly directional character (if any) is LTR.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether LTR directionality is detected using the first
+ *     strongly-directional character method.
+ * @deprecated Use startsWithLtr.
+ */
+goog.i18n.bidi.isLtrText = goog.i18n.bidi.startsWithLtr;
+
+
+/**
+ * Regular expression to check if a string looks like something that must
+ * always be LTR even in RTL text, e.g. a URL. When estimating the
+ * directionality of text containing these, we treat these as weakly LTR,
+ * like numbers.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.isRequiredLtrRe_ = /^http:\/\/.*/;
+
+
+/**
+ * Check whether the input string either contains no strongly directional
+ * characters or looks like a url.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether neutral directionality is detected.
+ */
+goog.i18n.bidi.isNeutralText = function(str, opt_isHtml) {
+  str = goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml);
+  return goog.i18n.bidi.isRequiredLtrRe_.test(str) ||
+      !goog.i18n.bidi.hasAnyLtr(str) && !goog.i18n.bidi.hasAnyRtl(str);
+};
+
+
+/**
+ * Regular expressions to check if the last strongly-directional character in a
+ * piece of text is LTR.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.ltrExitDirCheckRe_ = new RegExp(
+    '[' + goog.i18n.bidi.ltrChars_ + '][^' + goog.i18n.bidi.rtlChars_ + ']*$');
+
+
+/**
+ * Regular expressions to check if the last strongly-directional character in a
+ * piece of text is RTL.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rtlExitDirCheckRe_ = new RegExp(
+    '[' + goog.i18n.bidi.rtlChars_ + '][^' + goog.i18n.bidi.ltrChars_ + ']*$');
+
+
+/**
+ * Check if the exit directionality a piece of text is LTR, i.e. if the last
+ * strongly-directional character in the string is LTR.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether LTR exit directionality was detected.
+ */
+goog.i18n.bidi.endsWithLtr = function(str, opt_isHtml) {
+  return goog.i18n.bidi.ltrExitDirCheckRe_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Check if the exit directionality a piece of text is LTR, i.e. if the last
+ * strongly-directional character in the string is LTR.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether LTR exit directionality was detected.
+ * @deprecated Use endsWithLtr.
+ */
+goog.i18n.bidi.isLtrExitText = goog.i18n.bidi.endsWithLtr;
+
+
+/**
+ * Check if the exit directionality a piece of text is RTL, i.e. if the last
+ * strongly-directional character in the string is RTL.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether RTL exit directionality was detected.
+ */
+goog.i18n.bidi.endsWithRtl = function(str, opt_isHtml) {
+  return goog.i18n.bidi.rtlExitDirCheckRe_.test(
+      goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml));
+};
+
+
+/**
+ * Check if the exit directionality a piece of text is RTL, i.e. if the last
+ * strongly-directional character in the string is RTL.
+ * @param {string} str String being checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether RTL exit directionality was detected.
+ * @deprecated Use endsWithRtl.
+ */
+goog.i18n.bidi.isRtlExitText = goog.i18n.bidi.endsWithRtl;
+
+
+/**
+ * A regular expression for matching right-to-left language codes.
+ * See {@link #isRtlLanguage} for the design.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rtlLocalesRe_ = new RegExp(
+    '^(ar|ckb|dv|he|iw|fa|nqo|ps|sd|ug|ur|yi|' +
+        '.*[-_](Arab|Hebr|Thaa|Nkoo|Tfng))' +
+        '(?!.*[-_](Latn|Cyrl)($|-|_))($|-|_)',
+    'i');
+
+
+/**
+ * Check if a BCP 47 / III language code indicates an RTL language, i.e. either:
+ * - a language code explicitly specifying one of the right-to-left scripts,
+ *   e.g. "az-Arab", or<p>
+ * - a language code specifying one of the languages normally written in a
+ *   right-to-left script, e.g. "fa" (Farsi), except ones explicitly specifying
+ *   Latin or Cyrillic script (which are the usual LTR alternatives).<p>
+ * The list of right-to-left scripts appears in the 100-199 range in
+ * http://www.unicode.org/iso15924/iso15924-num.html, of which Arabic and
+ * Hebrew are by far the most widely used. We also recognize Thaana, N'Ko, and
+ * Tifinagh, which also have significant modern usage. The rest (Syriac,
+ * Samaritan, Mandaic, etc.) seem to have extremely limited or no modern usage
+ * and are not recognized to save on code size.
+ * The languages usually written in a right-to-left script are taken as those
+ * with Suppress-Script: Hebr|Arab|Thaa|Nkoo|Tfng  in
+ * http://www.iana.org/assignments/language-subtag-registry,
+ * as well as Central (or Sorani) Kurdish (ckb), Sindhi (sd) and Uyghur (ug).
+ * Other subtags of the language code, e.g. regions like EG (Egypt), are
+ * ignored.
+ * @param {string} lang BCP 47 (a.k.a III) language code.
+ * @return {boolean} Whether the language code is an RTL language.
+ */
+goog.i18n.bidi.isRtlLanguage = function(lang) {
+  return goog.i18n.bidi.rtlLocalesRe_.test(lang);
+};
+
+
+/**
+ * Regular expression for bracket guard replacement in text.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.bracketGuardTextRe_ =
+    /(\(.*?\)+)|(\[.*?\]+)|(\{.*?\}+)|(<.*?>+)/g;
+
+
+/**
+ * Apply bracket guard using LRM and RLM. This is to address the problem of
+ * messy bracket display frequently happens in RTL layout.
+ * This function works for plain text, not for HTML. In HTML, the opening
+ * bracket might be in a different context than the closing bracket (such as
+ * an attribute value).
+ * @param {string} s The string that need to be processed.
+ * @param {boolean=} opt_isRtlContext specifies default direction (usually
+ *     direction of the UI).
+ * @return {string} The processed string, with all bracket guarded.
+ */
+goog.i18n.bidi.guardBracketInText = function(s, opt_isRtlContext) {
+  var useRtl = opt_isRtlContext === undefined ? goog.i18n.bidi.hasAnyRtl(s) :
+                                                opt_isRtlContext;
+  var mark = useRtl ? goog.i18n.bidi.Format.RLM : goog.i18n.bidi.Format.LRM;
+  return s.replace(goog.i18n.bidi.bracketGuardTextRe_, mark + '$&' + mark);
+};
+
+
+/**
+ * Enforce the html snippet in RTL directionality regardless overall context.
+ * If the html piece was enclosed by tag, dir will be applied to existing
+ * tag, otherwise a span tag will be added as wrapper. For this reason, if
+ * html snippet start with with tag, this tag must enclose the whole piece. If
+ * the tag already has a dir specified, this new one will override existing
+ * one in behavior (tested on FF and IE).
+ * @param {string} html The string that need to be processed.
+ * @return {string} The processed string, with directionality enforced to RTL.
+ */
+goog.i18n.bidi.enforceRtlInHtml = function(html) {
+  if (html.charAt(0) == '<') {
+    return html.replace(/<\w+/, '$& dir=rtl');
+  }
+  // '\n' is important for FF so that it won't incorrectly merge span groups
+  return '\n<span dir=rtl>' + html + '</span>';
+};
+
+
+/**
+ * Enforce RTL on both end of the given text piece using unicode BiDi formatting
+ * characters RLE and PDF.
+ * @param {string} text The piece of text that need to be wrapped.
+ * @return {string} The wrapped string after process.
+ */
+goog.i18n.bidi.enforceRtlInText = function(text) {
+  return goog.i18n.bidi.Format.RLE + text + goog.i18n.bidi.Format.PDF;
+};
+
+
+/**
+ * Enforce the html snippet in RTL directionality regardless overall context.
+ * If the html piece was enclosed by tag, dir will be applied to existing
+ * tag, otherwise a span tag will be added as wrapper. For this reason, if
+ * html snippet start with with tag, this tag must enclose the whole piece. If
+ * the tag already has a dir specified, this new one will override existing
+ * one in behavior (tested on FF and IE).
+ * @param {string} html The string that need to be processed.
+ * @return {string} The processed string, with directionality enforced to RTL.
+ */
+goog.i18n.bidi.enforceLtrInHtml = function(html) {
+  if (html.charAt(0) == '<') {
+    return html.replace(/<\w+/, '$& dir=ltr');
+  }
+  // '\n' is important for FF so that it won't incorrectly merge span groups
+  return '\n<span dir=ltr>' + html + '</span>';
+};
+
+
+/**
+ * Enforce LTR on both end of the given text piece using unicode BiDi formatting
+ * characters LRE and PDF.
+ * @param {string} text The piece of text that need to be wrapped.
+ * @return {string} The wrapped string after process.
+ */
+goog.i18n.bidi.enforceLtrInText = function(text) {
+  return goog.i18n.bidi.Format.LRE + text + goog.i18n.bidi.Format.PDF;
+};
+
+
+/**
+ * Regular expression to find dimensions such as "padding: .3 0.4ex 5px 6;"
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.dimensionsRe_ =
+    /:\s*([.\d][.\w]*)\s+([.\d][.\w]*)\s+([.\d][.\w]*)\s+([.\d][.\w]*)/g;
+
+
+/**
+ * Regular expression for left.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.leftRe_ = /left/gi;
+
+
+/**
+ * Regular expression for right.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.rightRe_ = /right/gi;
+
+
+/**
+ * Placeholder regular expression for swapping.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.tempRe_ = /%%%%/g;
+
+
+/**
+ * Swap location parameters and 'left'/'right' in CSS specification. The
+ * processed string will be suited for RTL layout. Though this function can
+ * cover most cases, there are always exceptions. It is suggested to put
+ * those exceptions in separate group of CSS string.
+ * @param {string} cssStr CSS spefication string.
+ * @return {string} Processed CSS specification string.
+ */
+goog.i18n.bidi.mirrorCSS = function(cssStr) {
+  return cssStr
+      .
+      // reverse dimensions
+      replace(goog.i18n.bidi.dimensionsRe_, ':$1 $4 $3 $2')
+      .replace(goog.i18n.bidi.leftRe_, '%%%%')
+      .  // swap left and right
+      replace(goog.i18n.bidi.rightRe_, goog.i18n.bidi.LEFT)
+      .replace(goog.i18n.bidi.tempRe_, goog.i18n.bidi.RIGHT);
+};
+
+
+/**
+ * Regular expression for hebrew double quote substitution, finding quote
+ * directly after hebrew characters.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.doubleQuoteSubstituteRe_ = /([\u0591-\u05f2])"/g;
+
+
+/**
+ * Regular expression for hebrew single quote substitution, finding quote
+ * directly after hebrew characters.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.singleQuoteSubstituteRe_ = /([\u0591-\u05f2])'/g;
+
+
+/**
+ * Replace the double and single quote directly after a Hebrew character with
+ * GERESH and GERSHAYIM. In such case, most likely that's user intention.
+ * @param {string} str String that need to be processed.
+ * @return {string} Processed string with double/single quote replaced.
+ */
+goog.i18n.bidi.normalizeHebrewQuote = function(str) {
+  return str.replace(goog.i18n.bidi.doubleQuoteSubstituteRe_, '$1\u05f4')
+      .replace(goog.i18n.bidi.singleQuoteSubstituteRe_, '$1\u05f3');
+};
+
+
+/**
+ * Regular expression to split a string into "words" for directionality
+ * estimation based on relative word counts.
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.wordSeparatorRe_ = /\s+/;
+
+
+/**
+ * Regular expression to check if a string contains any numerals. Used to
+ * differentiate between completely neutral strings and those containing
+ * numbers, which are weakly LTR.
+ *
+ * Native Arabic digits (\u0660 - \u0669) are not included because although they
+ * do flow left-to-right inside a number, this is the case even if the  overall
+ * directionality is RTL, and a mathematical expression using these digits is
+ * supposed to flow right-to-left overall, including unary plus and minus
+ * appearing to the right of a number, and this does depend on the overall
+ * directionality being RTL. The digits used in Farsi (\u06F0 - \u06F9), on the
+ * other hand, are included, since Farsi math (including unary plus and minus)
+ * does flow left-to-right.
+ *
+ * @type {RegExp}
+ * @private
+ */
+goog.i18n.bidi.hasNumeralsRe_ = /[\d\u06f0-\u06f9]/;
+
+
+/**
+ * This constant controls threshold of RTL directionality.
+ * @type {number}
+ * @private
+ */
+goog.i18n.bidi.rtlDetectionThreshold_ = 0.40;
+
+
+/**
+ * Estimates the directionality of a string based on relative word counts.
+ * If the number of RTL words is above a certain percentage of the total number
+ * of strongly directional words, returns RTL.
+ * Otherwise, if any words are strongly or weakly LTR, returns LTR.
+ * Otherwise, returns UNKNOWN, which is used to mean "neutral".
+ * Numbers are counted as weakly LTR.
+ * @param {string} str The string to be checked.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {goog.i18n.bidi.Dir} Estimated overall directionality of {@code str}.
+ */
+goog.i18n.bidi.estimateDirection = function(str, opt_isHtml) {
+  var rtlCount = 0;
+  var totalCount = 0;
+  var hasWeaklyLtr = false;
+  var tokens = goog.i18n.bidi.stripHtmlIfNeeded_(str, opt_isHtml)
+                   .split(goog.i18n.bidi.wordSeparatorRe_);
+  for (var i = 0; i < tokens.length; i++) {
+    var token = tokens[i];
+    if (goog.i18n.bidi.startsWithRtl(token)) {
+      rtlCount++;
+      totalCount++;
+    } else if (goog.i18n.bidi.isRequiredLtrRe_.test(token)) {
+      hasWeaklyLtr = true;
+    } else if (goog.i18n.bidi.hasAnyLtr(token)) {
+      totalCount++;
+    } else if (goog.i18n.bidi.hasNumeralsRe_.test(token)) {
+      hasWeaklyLtr = true;
+    }
+  }
+
+  return totalCount == 0 ?
+      (hasWeaklyLtr ? goog.i18n.bidi.Dir.LTR : goog.i18n.bidi.Dir.NEUTRAL) :
+      (rtlCount / totalCount > goog.i18n.bidi.rtlDetectionThreshold_ ?
+           goog.i18n.bidi.Dir.RTL :
+           goog.i18n.bidi.Dir.LTR);
+};
+
+
+/**
+ * Check the directionality of a piece of text, return true if the piece of
+ * text should be laid out in RTL direction.
+ * @param {string} str The piece of text that need to be detected.
+ * @param {boolean=} opt_isHtml Whether str is HTML / HTML-escaped.
+ *     Default: false.
+ * @return {boolean} Whether this piece of text should be laid out in RTL.
+ */
+goog.i18n.bidi.detectRtlDirectionality = function(str, opt_isHtml) {
+  return goog.i18n.bidi.estimateDirection(str, opt_isHtml) ==
+      goog.i18n.bidi.Dir.RTL;
+};
+
+
+/**
+ * Sets text input element's directionality and text alignment based on a
+ * given directionality. Does nothing if the given directionality is unknown or
+ * neutral.
+ * @param {Element} element Input field element to set directionality to.
+ * @param {goog.i18n.bidi.Dir|number|boolean|null} dir Desired directionality,
+ *     given in one of the following formats:
+ *     1. A goog.i18n.bidi.Dir constant.
+ *     2. A number (positive = LRT, negative = RTL, 0 = neutral).
+ *     3. A boolean (true = RTL, false = LTR).
+ *     4. A null for unknown directionality.
+ */
+goog.i18n.bidi.setElementDirAndAlign = function(element, dir) {
+  if (element) {
+    dir = goog.i18n.bidi.toDir(dir);
+    if (dir) {
+      element.style.textAlign = dir == goog.i18n.bidi.Dir.RTL ?
+          goog.i18n.bidi.RIGHT :
+          goog.i18n.bidi.LEFT;
+      element.dir = dir == goog.i18n.bidi.Dir.RTL ? 'rtl' : 'ltr';
+    }
+  }
+};
+
+
+/**
+ * Sets element dir based on estimated directionality of the given text.
+ * @param {!Element} element
+ * @param {string} text
+ */
+goog.i18n.bidi.setElementDirByTextDirectionality = function(element, text) {
+  switch (goog.i18n.bidi.estimateDirection(text)) {
+    case (goog.i18n.bidi.Dir.LTR):
+      element.dir = 'ltr';
+      break;
+    case (goog.i18n.bidi.Dir.RTL):
+      element.dir = 'rtl';
+      break;
+    default:
+      // Default for no direction, inherit from document.
+      element.removeAttribute('dir');
+  }
+};
+
+
+
+/**
+ * Strings that have an (optional) known direction.
+ *
+ * Implementations of this interface are string-like objects that carry an
+ * attached direction, if known.
+ * @interface
+ */
+goog.i18n.bidi.DirectionalString = function() {};
+
+
+/**
+ * Interface marker of the DirectionalString interface.
+ *
+ * This property can be used to determine at runtime whether or not an object
+ * implements this interface.  All implementations of this interface set this
+ * property to {@code true}.
+ * @type {boolean}
+ */
+goog.i18n.bidi.DirectionalString.prototype
+    .implementsGoogI18nBidiDirectionalString;
+
+
+/**
+ * Retrieves this object's known direction (if any).
+ * @return {?goog.i18n.bidi.Dir} The known direction. Null if unknown.
+ */
+goog.i18n.bidi.DirectionalString.prototype.getDirection;