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diff --git a/chromium/chrome/browser/resources/chromeos/chromevox/walkers/abstract_node_walker.js b/chromium/chrome/browser/resources/chromeos/chromevox/walkers/abstract_node_walker.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 base class for walkers that have a concept of lowest-level
+ * node. Base classes must override the stopNodeDescent method to define
+ * what a lowest-level node is. Then this walker will use those nodes as the
+ * set of valid CursorSelections.
+ */
+
+
+goog.provide('cvox.AbstractNodeWalker');
+
+goog.require('cvox.AbstractWalker');
+goog.require('cvox.CursorSelection');
+goog.require('cvox.DomUtil');
+
+/**
+ * @constructor
+ * @extends {cvox.AbstractWalker}
+ */
+cvox.AbstractNodeWalker = function() {
+  goog.base(this);
+
+  /**
+   * To keep track of and break infinite loops when trying to call next on
+   * a body that does not DomUtil.hasContent().
+   * @type {boolean}
+   * @private
+   */
+  this.wasBegin_ = false;
+};
+goog.inherits(cvox.AbstractNodeWalker, cvox.AbstractWalker);
+
+/**
+ * @override
+ */
+cvox.AbstractNodeWalker.prototype.next = function(sel) {
+  var r = sel.isReversed();
+  var node = sel.end.node || document.body;
+
+  do {
+    node = cvox.DomUtil.directedNextLeafLikeNode(node, r,
+        goog.bind(this.stopNodeDescent, this));
+    if (!node) {
+      return null;
+    }
+    // and repeat all of the above until we have a node that is not empty
+  } while (node && !cvox.DomUtil.hasContent(node));
+
+  return cvox.CursorSelection.fromNode(node).setReversed(r);
+};
+
+/**
+ * @override
+ */
+cvox.AbstractNodeWalker.prototype.sync = function(sel) {
+  var ret = this.privateSync_(sel);
+  this.wasBegin_ = false;
+  return ret;
+};
+
+
+/**
+ * Private version of sync to ensure that when a body has no content, we
+ * don't do an infinite loop trying to find an empty node.
+ * @param {!cvox.CursorSelection} sel The selection.
+ * @return {cvox.CursorSelection} The synced selection.
+ * @private
+ */
+cvox.AbstractNodeWalker.prototype.privateSync_ = function(sel) {
+  var r = sel.isReversed();
+
+  if (sel.equals(cvox.CursorSelection.fromBody())) {
+    if (this.wasBegin_) {
+      // if body is empty, we return just the body selection
+      return cvox.CursorSelection.fromBody().setReversed(r);
+    }
+    this.wasBegin_ = true;
+  }
+
+  var node = sel.start.node;
+
+  while (node != document.body && node.parentNode &&
+      this.stopNodeDescent(node.parentNode)) {
+    node = node.parentNode;
+  }
+
+  while (!this.stopNodeDescent(node)) {
+    node = cvox.DomUtil.directedFirstChild(node, r);
+  }
+
+  var n = cvox.CursorSelection.fromNode(node);
+  if (!cvox.DomUtil.hasContent(node)) {
+    var n = this.next(/** @type {!cvox.CursorSelection} */
+        (cvox.CursorSelection.fromNode(node)).setReversed(r));
+  }
+  if (n) {
+    return n.setReversed(r);
+  }
+  return this.begin({reversed: r});
+};
+
+/**
+ * Returns true if this is "a leaf node" or lower. That is,
+ * it is at the lowest valid level or lower for this granularity.
+ * RESTRICTION: true for a node => true for all child nodes
+ * RESTRICTION: true if node has no children
+ * @param {!Node} node The node to check.
+ * @return {boolean} true if this is at the "leaf node" level or lower
+ * for this granularity.
+ * @protected
+ */
+cvox.AbstractNodeWalker.prototype.stopNodeDescent = goog.abstractMethod;