Enable DumpAccessibilityTree tests to use cross-process iframes.

content/browser/accessibility/browser_accessibility_manager.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/browser/accessibility/browser_accessibility_manager.h"
 
 #include <stddef.h>
 
 #include "base/logging.h"
 #include "build/build_config.h"
@@ skipping 597 matching lines @@
   if (ax_tree_id_changed || root_changed) {
     BrowserAccessibility* parent = GetParentNodeFromParentTree();
     if (parent) {
       parent->OnDataChanged();
       parent->manager()->NotifyAccessibilityEvent(
           ui::AX_EVENT_CHILDREN_CHANGED, parent);
     }
   }
 }
 
-BrowserAccessibilityDelegate*
-    BrowserAccessibilityManager::GetDelegateFromRootManager() {
+BrowserAccessibilityManager* BrowserAccessibilityManager::GetRootManager() {
   if (!GetRoot())

[David Tseng, 2016/01/07 00:02:29]

When does this happen?

[dmazzoni, 2016/01/07 19:19:08]

In the middle of a tree update when we call something like OnNodeWillBeDeleted.
I've thought about rewriting that so that it precomputes the nodes that would be
deleted so it doesn't ever have to call back when the tree is broken.

     return nullptr;
   int parent_tree_id = GetTreeData().parent_tree_id;
   BrowserAccessibilityManager* parent_manager =
       BrowserAccessibilityManager::FromID(parent_tree_id);
   if (parent_manager)
-    return parent_manager->GetDelegateFromRootManager();
-  return delegate();
+    return parent_manager->GetRootManager();
+  return this;
+}
+
+BrowserAccessibilityDelegate*
+    BrowserAccessibilityManager::GetDelegateFromRootManager() {
+  BrowserAccessibilityManager* root_manager = GetRootManager();
+  if (root_manager)
+    return root_manager->delegate();
+  return nullptr;
 }
 
 ui::AXTreeUpdate
 BrowserAccessibilityManager::SnapshotAXTreeForTesting() {
   scoped_ptr<ui::AXTreeSource<const ui::AXNode*,
                               ui::AXNodeData,
                               ui::AXTreeData> > tree_source(
       tree_->CreateTreeSource());
   ui::AXTreeSerializer<const ui::AXNode*,
                        ui::AXNodeData,
                        ui::AXTreeData> serializer(tree_source.get());
   ui::AXTreeUpdate update;
   serializer.SerializeChanges(tree_->root(), &update);
   return update;
 }
 
 }  // namespace content