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 596 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())
     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