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diff --git a/chromium/chrome/browser/resources/chromeos/chromevox/common/page_selection.js b/chromium/chrome/browser/resources/chromeos/chromevox/common/page_selection.js
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+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview A class representing a DOM selection conveyed through
+ * CursorSelection idioms.
+ * A PageSelection is just a DOM selection. The class itself manages a single
+ * CursorSelection that surrounds a fragment on the page. It also provides an
+ * extend operation to either grow or shrink the selection given a
+ * CursorSelection. The class handles correctly moving the internal
+ * CursorSelection and providing immediate access to a full description of the
+ * selection at any time.
+ */
+
+goog.provide('cvox.PageSelection');
+
+goog.require('cvox.AbstractEarcons');
+goog.require('cvox.CursorSelection');
+goog.require('cvox.NavDescription');
+
+/**
+ * @constructor
+ * @param {!cvox.CursorSelection} sel The initial selection.
+ */
+cvox.PageSelection = function(sel) {
+  this.sel_ = sel.clone();
+  this.sel_.select();
+  this.wasBegin_ = true;
+};
+
+
+/**
+ * Gets a description for the DOM selection during the course of navigation.
+ * @param {cvox.AbstractShifter} navShifter Used to obtain walker-based
+ * descriptions.
+ * @param {!cvox.CursorSelection} prevSel Previous CursorSelection in
+ * navigation.
+ * @param {!cvox.CursorSelection} curSel Current CursorSelection in navigation.
+ * @return {Array.<cvox.NavDescription>} The new description.
+ */
+cvox.PageSelection.prototype.getDescription =
+    function(navShifter, prevSel, curSel) {
+  var desc = [];
+  if (this.sel_.isReversed() != curSel.isReversed()) {
+    // A shrinking selection.
+    desc = navShifter.getDescription(curSel, prevSel);
+    desc[0].annotation = cvox.ChromeVox.msgs.getMsg('describe_unselected');
+    desc[0].pushEarcon(cvox.AbstractEarcons.SELECTION_REVERSE);
+  } else {
+    // A growing selection.
+    desc = navShifter.getDescription(prevSel, curSel);
+    desc[0].annotation = cvox.ChromeVox.msgs.getMsg('describe_selected');
+    desc[0].pushEarcon(cvox.AbstractEarcons.SELECTION);
+    if (!this.wasBegin_ && this.sel_.absEquals(curSel.clone().normalize())) {
+      // A selection has inverted across the start cursor. Describe it.
+      var prevDesc = navShifter.getDescription(curSel, prevSel);
+      prevDesc[0].annotation =
+          cvox.ChromeVox.msgs.getMsg('describe_unselected');
+      prevDesc[0].pushEarcon(cvox.AbstractEarcons.SELECTION_REVERSE);
+      prevDesc[0].pushEarcon(cvox.AbstractEarcons.WRAP);
+      desc = prevDesc.concat(desc);
+    }
+  }
+  return desc;
+};
+
+
+/**
+ * Gets a full description for the entire DOM selection.
+ * Use this description when you want to describe the entire selection
+ * represented by this instance.
+ *
+ * @return {Array.<cvox.NavDescription>} The new description.
+ */
+cvox.PageSelection.prototype.getFullDescription = function() {
+  return [new cvox.NavDescription(
+      {text: window.getSelection().toString(),
+       context: cvox.ChromeVox.msgs.getMsg('selection_is')})];
+};
+
+
+/**
+ * Extends this selection.
+ * @param {!cvox.CursorSelection} sel Extend DOM selection to the selection.
+ * @return {boolean} True if the extension occurred, false if the PageSelection
+ * was reset to sel.
+ */
+cvox.PageSelection.prototype.extend = function(sel) {
+  if (!this.sel_.directedBefore(sel)) {
+    // Do not allow for crossed selections. This restarts a page selection that
+    // has been collapsed. This occurs when two CursorSelection's point away
+    // from one another.
+    this.sel_ = sel.clone();
+  } else {
+    // Otherwise, it is assumed that the CursorSelection's are in directed
+    // document order. The CursorSelection's are either pointing in the same
+    // direction or towards one another. In the first case, shrink/extend this
+    // PageSelection to the end of "sel". In the second case, shrink/extend this
+    // PageSelection to the start of "sel".
+    this.sel_.end = this.sel_.isReversed() == sel.isReversed() ?
+        sel.end.clone() : sel.start.clone();
+  }
+  this.sel_.select();
+  this.wasBegin_ = false;
+  return !this.sel_.absEquals(sel);
+};