Make cvox2 feedback more robust when focusing a text field.

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js

 // 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 The entry point for all ChromeVox2 related code for the
  * background page.
  */
 
 goog.provide('Background');
@@ skipping 71 matching lines @@
     focus: this.onFocus,
     hover: this.onEventDefault,
     loadComplete: this.onLoadComplete,
     menuStart: this.onEventDefault,
     menuEnd: this.onEventDefault,
     textChanged: this.onTextOrTextSelectionChanged,
     textSelectionChanged: this.onTextOrTextSelectionChanged,
     valueChanged: this.onValueChanged
   };
 
+  /**
+   * The object that speaks changes to an editable text field.
+   * @type {?cvox.ChromeVoxEditableTextBase}
+   */
+  this.editableTextHandler_ = null;
+
   chrome.automation.getDesktop(this.onGotDesktop);
 
   // Handle messages directed to the Next background page.
   cvox.ExtensionBridge.addMessageListener(function(msg, port) {
     var target = msg['target'];
     var action = msg['action'];
 
     switch (target) {
       case 'next':
         if (action == 'getIsClassicEnabled') {
@@ skipping 362 matching lines @@
                                          Dir.FORWARD,
                                          AutomationPredicate.focused) || node;
 
       // Fall back to the first leaf node in the document.
       if (node.role == RoleType.rootWebArea) {
         node = AutomationUtil.findNodePost(node,
                                            Dir.FORWARD,
                                            AutomationPredicate.leaf);
       }
     }
+
+    if (evt.target.role == RoleType.textField)
+      this.createEditableTextHandlerIfNeeded_(evt.target);
+
     this.onEventDefault({target: node, type: 'focus'});
   },
 
   /**
    * Provides all feedback once a load complete event fires.
    * @param {Object} evt
    */
   onLoadComplete: function(evt) {
     this.setupChromeVoxVariants_(evt.target.docUrl);
 
@@ skipping 42 matching lines @@
       return;
 
     if (!evt.target.state.focused)
       return;
 
     if (!this.currentRange_) {
       this.onEventDefault(evt);
       this.currentRange_ = cursors.Range.fromNode(evt.target);
     }
 
+    this.createEditableTextHandlerIfNeeded_(evt.target);
     var textChangeEvent = new cvox.TextChangeEvent(
         evt.target.value,
         evt.target.textSelStart,
         evt.target.textSelEnd,
         true);  // triggered by user
-    if (!this.editableTextHandler ||
-        evt.target != this.currentRange_.start.node) {
-      this.editableTextHandler =
-          new cvox.ChromeVoxEditableTextBase(
-              textChangeEvent.value,
-              textChangeEvent.start,
-              textChangeEvent.end,
-              evt.target.state['protected'],
-              cvox.ChromeVox.tts);
 
-      // Ignore the first text selection changed event which gets fired after
-      // the focus event.
-      return;
-    }
+    this.editableTextHandler_.changed(textChangeEvent);
 
-    this.editableTextHandler.changed(textChangeEvent);
     new Output().withBraille(
             this.currentRange_, null, evt.type)
         .go();
   },
 
   /**
    * Provides all feedback once a value changed event fires.
    * @param {Object} evt
    */
   onValueChanged: function(evt) {
@@ skipping 171 matching lines @@
     });
     if (!actionNode)
       return;
     if (actionNode.role === RoleType.inlineTextBox)
       actionNode = actionNode.parent;
     actionNode.doDefault();
     if (selectionSpan) {
       var start = text.getSpanStart(selectionSpan);
       actionNode.setSelection(position - start, position - start);
     }
+  },
+
+  /**
+   * Create an editable text handler for the given node if needed.
+   * @param {Object} node
+   */
+  createEditableTextHandlerIfNeeded_: function(node) {
+    if (!this.editableTextHandler_ || node != this.currentRange_.start.node) {
+      var start = node.textSelStart;
+      var end = node.textSelEnd;
+      if (start > end) {
+        var tempOffset = end;
+        end = start;
+        start = tempOffset;
+      }
+
+      this.editableTextHandler_ =
+          new cvox.ChromeVoxEditableTextBase(
+              node.value,
+              start,
+              end,
+              node.state.protected,
+              cvox.ChromeVox.tts);
+    }
   }
 };
 
 /** @type {Background} */
 global.backgroundObj = new Background();
 
 });  // goog.scope