Initial support for accessible text fields and focus tracking in ARC++

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

 // Copyright 2015 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 Handles automation from a desktop automation node.
  */
 
 goog.provide('DesktopAutomationHandler');
 
@@ skipping 378 matching lines @@
       this.onEditableChanged_(evt);
   },
 
   /**
    * Provides all feedback once a change event in a text field fires.
    * @param {!AutomationEvent} evt
    * @private
    */
   onEditableChanged_: function(evt) {
     var topRoot = AutomationUtil.getTopLevelRoot(evt.target);
-    if (!evt.target.state.focused ||
-        (topRoot &&
-            topRoot.parent &&
-            !topRoot.parent.state.focused))
+    if (topRoot && topRoot.parent && !topRoot.parent.state.focused)
+      return;
+
+    // Only process editable text events if either system or ChromeVox focus is

[dmazzoni, 2017/03/17 03:22:37]

I think this might break contenteditable if the selection start and end are both
children of the contenteditable root. Maybe walk up to the focused ancestor or
something?

[David Tseng, 2017/03/17 15:38:32]

Yeah, I think you're right. The issue is that on Android, the text field doesn't
actually get focus as we're currently computing it. I might think about
explicitly tracking focus on the Android end to help us from not doing this.
I'll try to do something there before this change since comparing ranges is
fragile.

+    // on the target.
+    if (!evt.target.state.focused &&
+        (!ChromeVoxState.instance.currentRange ||
+            ChromeVoxState.instance.currentRange.start.node != evt.target))
       return;
 
     if (!ChromeVoxState.instance.currentRange) {
       this.onEventDefault(evt);
       ChromeVoxState.instance.setCurrentRange(
           cursors.Range.fromNode(evt.target));
     }
 
     this.createTextEditHandlerIfNeeded_(evt.target);
 
@@ skipping 149 matching lines @@
 DesktopAutomationHandler.init_ = function() {
   chrome.automation.getDesktop(function(desktop) {
     ChromeVoxState.desktopAutomationHandler =
         new DesktopAutomationHandler(desktop);
   });
 };
 
 DesktopAutomationHandler.init_();
 
 });  // goog.scope