Always retarget blur events to the root of the focused node

chrome/renderer/resources/extensions/automation_custom_bindings.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.
 
 // Custom bindings for the automation API.
 var AutomationNode = require('automationNode').AutomationNode;
 var AutomationRootNode = require('automationNode').AutomationRootNode;
 var automation = require('binding').Binding.create('automation');
 var automationInternal =
     require('binding').Binding.create('automationInternal').generate();
@@ skipping 75 matching lines @@
     return privates(tree).impl.get(focusedNodeInfo.nodeId);
 };
 
 /**
  * Update automationUtil.focusedNode to be the node that currently has focus.
  */
 automationUtil.updateFocusedNode = function() {
   automationUtil.focusedNode = automationUtil.getFocus();
 };
 
+/**
+ * Updates the focus on blur.
+ */
+automationUtil.updateFocusedNodeOnBlur = function() {
+  var focus = automationUtil.getFocus();
+  automationUtil.focusedNode = focus ? focus.root : null;
+};
+
 automation.registerCustomHook(function(bindingsAPI) {
   var apiFunctions = bindingsAPI.apiFunctions;
 
   // TODO(aboxhall, dtseng): Make this return the speced AutomationRootNode obj.
   apiFunctions.setHandleRequest('getTree', function getTree(tabID, callback) {
     var routingID = GetRoutingID();
     StartCachingAccessibilityTrees();
 
     // enableTab() ensures the renderer for the active or specified tab has
     // accessibility enabled, and fetches its ax tree id to use as
@@ skipping 174 matching lines @@
 
   var isFocusEvent = false;
   if (eventParams.eventType == schema.EventType.focus) {
     isFocusEvent = true;
   } else if (eventParams.eventType == schema.EventType.blur) {
     // Work around an issue where Chrome sends us 'blur' events on the
     // root node when nothing has focus, we need to treat those as focus
     // events but otherwise not handle blur events specially.
     var node = privates(targetTree).impl.get(eventParams.targetID);
     if (node == node.root)
-      isFocusEvent = true;
+      automationUtil.updateFocusedNodeOnBlur();
   } else if (eventParams.eventType == schema.EventType.mediaStartedPlaying ||
       eventParams.eventType == schema.EventType.mediaStoppedPlaying) {
     // These events are global to the tree.
     eventParams.targetID = privates(targetTree).impl.id;
   }
 
   // When we get a focus event, ignore the actual event target, and instead
   // check what node has focus globally. If that represents a focus change,
   // fire a focus event on the correct target.
   if (isFocusEvent) {
@@ skipping 57 matching lines @@
 
 var binding = automation.generate();
 // Add additional accessibility bindings not specified in the automation IDL.
 // Accessibility and automation share some APIs (see
 // ui/accessibility/ax_enums.idl).
 forEach(schema, function(k, v) {
   binding[k] = v;
 });
 
 exports.$set('binding', binding);