Add a treeChange type to Automation

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 632 matching lines @@
     start_text_object = NextTextOnlyObject(start_text_object);
   }
   if (end_offset <= static_cast<int>(end_text_object->GetText().length()))
     text += end_text_object->GetText().substr(0, end_offset);
   else
     text += end_text_object->GetText();
 
   return text;
 }
 
+void BrowserAccessibilityManager::OnNodeDataWillChange(
+    ui::AXTree* tree,
+    const ui::AXNodeData& old_node_data,
+    const ui::AXNodeData& new_node_data) {}
+
 void BrowserAccessibilityManager::OnTreeDataChanged(ui::AXTree* tree) {
 }
 
 void BrowserAccessibilityManager::OnNodeWillBeDeleted(ui::AXTree* tree,
                                                       ui::AXNode* node) {
   DCHECK(node);
   if (id_wrapper_map_.find(node->id()) == id_wrapper_map_.end())
     return;
   GetFromAXNode(node)->Destroy();
   id_wrapper_map_.erase(node->id());
@@ skipping 70 matching lines @@
       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