Cross-process iframe accessibility.

content/renderer/accessibility/renderer_accessibility_complete.cc

 // Copyright (c) 2012 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/renderer_accessibility_complete.h"
 
 #include <queue>
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 178 matching lines @@
 
     // When we get a "selected children changed" event, Blink
     // doesn't also send us events for each child that changed
     // selection state, so make sure we re-send that whole subtree.
     if (event.event_type ==
         ui::AX_EVENT_SELECTED_CHILDREN_CHANGED) {
       serializer_.DeleteClientSubtree(obj);
     }
 
     AccessibilityHostMsg_EventParams event_msg;
+    tree_source_.CollectChildFrameIdMapping(

[ncarter (slow), 2014/05/02 19:10:02]

When the method SendPendingAccessibilityEvents returns, it seems that
tree_source_ will be left with two icky stack pointers into the corpse of
event_msg. Can we either give them a proper burial, or make the interface safer?

One possible solution would be to have the members of tree_source_ be maps (vs
map*'s) and after the maps are filled -- maybe at the end of SerializeChanges --
do a map::swap between the event_msg and the tree_source copies. That should be
as efficient, right?

+        &event_msg.guest_instance_ids,
+        &event_msg.frame_routing_ids);
     event_msg.event_type = event.event_type;
     event_msg.id = event.id;
     serializer_.SerializeChanges(obj, &event_msg.update);
     event_msgs.push_back(event_msg);
 
 #ifndef NDEBUG
     VLOG(0) << "Accessibility update: \n"
             << "routing id=" << routing_id()
             << " event="
             << AccessibilityEventToString(event.event_type)
@@ skipping 166 matching lines @@
     render_view()->GetWebView()->clearFocusedElement();
   else
     obj.setFocused(true);
 }
 
 void RendererAccessibilityComplete::OnFatalError() {
   CHECK(false) << "Invalid accessibility tree.";
 }
 
 }  // namespace content