Work around <webview> focus bugs by enforcing focus event invariants.

content/renderer/accessibility/blink_ax_enum_conversion.cc

 // Copyright (c) 2013 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.
 
 #include "content/renderer/accessibility/blink_ax_enum_conversion.h"
 
 #include "base/logging.h"
 
 namespace content {
 
@@ skipping 334 matching lines @@
 ui::AXEvent AXEventFromBlink(blink::WebAXEvent event) {
   switch (event) {
     case blink::WebAXEventActiveDescendantChanged:
       return ui::AX_EVENT_ACTIVEDESCENDANTCHANGED;
     case blink::WebAXEventAlert:
       return ui::AX_EVENT_ALERT;
     case blink::WebAXEventAriaAttributeChanged:
       return ui::AX_EVENT_ARIA_ATTRIBUTE_CHANGED;
     case blink::WebAXEventAutocorrectionOccured:
       return ui::AX_EVENT_AUTOCORRECTION_OCCURED;
+    case blink::WebAXEventBlur:
+      return ui::AX_EVENT_BLUR;
     case blink::WebAXEventCheckedStateChanged:
       return ui::AX_EVENT_CHECKED_STATE_CHANGED;
     case blink::WebAXEventChildrenChanged:
       return ui::AX_EVENT_CHILDREN_CHANGED;
     case blink::WebAXEventFocus:
       return ui::AX_EVENT_FOCUS;
     case blink::WebAXEventHover:
       return ui::AX_EVENT_HOVER;
     case blink::WebAXEventInvalidStatusChanged:
       return ui::AX_EVENT_INVALID_STATUS_CHANGED;
@@ skipping 103 matching lines @@
     case blink::WebAXSortDirectionOther:
       return ui::AX_SORT_DIRECTION_OTHER;
     default:
       NOTREACHED();
   }
 
   return ui::AX_SORT_DIRECTION_NONE;
 }
 
 }  // Namespace content.