Track all changed nodes during an update

chrome/renderer/extensions/automation_internal_custom_bindings.cc

 // Copyright 2014 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 "chrome/renderer/extensions/automation_internal_custom_bindings.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 1079 matching lines @@
     const ui::AXNodeData& new_node_data) {
   if (old_node_data.GetStringAttribute(ui::AX_ATTR_NAME) !=
       new_node_data.GetStringAttribute(ui::AX_ATTR_NAME))
     text_changed_node_ids_.push_back(new_node_data.id);
 }
 
 void AutomationInternalCustomBindings::OnTreeDataChanged(ui::AXTree* tree) {}
 
 void AutomationInternalCustomBindings::OnNodeWillBeDeleted(ui::AXTree* tree,
                                                            ui::AXNode* node) {
-  SendTreeChangeEvent(
-      api::automation::TREE_CHANGE_TYPE_NODEREMOVED,

[dmazzoni, 2016/06/20 22:47:23]

I think you still need to call this, otherwise we
can't support live regions that specifically want
notifications for removed nodes (aria-relevant="removals").

Perhaps ChromeVox's live_regions.js should handle the
"nodeRemoved" tree change but defer actually processing it,
and only handle it if the node was not reparented?

Note that automation needs to fire the tree change event now
because if we call it any later, the node won't exist anymore.

-      tree, node);
   deleted_node_ids_.push_back(node->id());
+
+  // Don't do anything here because the update may reparent and not delete this
+  // node.
 }
 
 void AutomationInternalCustomBindings::OnSubtreeWillBeDeleted(
     ui::AXTree* tree,
     ui::AXNode* node) {
-  // This isn't strictly needed, as OnNodeWillBeDeleted will already be
-  // called. We could send a JS event for this only if it turns out to
-  // be needed for something.
+  // Don't do anything here because the update may reparent and not delete this
+  // subtree.
 }
 
 void AutomationInternalCustomBindings::OnNodeCreated(ui::AXTree* tree,
                                                      ui::AXNode* node) {
   // Not needed, this is called in the middle of an update so it's not
   // safe to trigger JS from here. Wait for the notification in
   // OnAtomicUpdateFinished instead.
 }
 
 void AutomationInternalCustomBindings::OnNodeChanged(ui::AXTree* tree,
@@ skipping 22 matching lines @@
       case SUBTREE_CREATED:
         SendTreeChangeEvent(
             api::automation::TREE_CHANGE_TYPE_SUBTREECREATED,
             tree, node);
         break;
       case NODE_CHANGED:
         SendTreeChangeEvent(
             api::automation::TREE_CHANGE_TYPE_NODECHANGED,
             tree, node);
         break;
-      // Unhandled.
       case NODE_REPARENTED:
       case SUBTREE_REPARENTED:
+        auto iter = std::find(deleted_node_ids_.begin(),
+                              deleted_node_ids_.end(), node->id());
+        if (iter != deleted_node_ids_.end())
+          deleted_node_ids_.erase(iter);
         break;
     }
   }
 
   for (int id : text_changed_node_ids_) {
     SendTreeChangeEvent(api::automation::TREE_CHANGE_TYPE_TEXTCHANGED, tree,
                         tree->GetFromId(id));
   }
   text_changed_node_ids_.clear();
 }
@@ skipping 92 matching lines @@
   v8::Local<v8::Array> args(v8::Array::New(GetIsolate(), 2U));
   args->Set(0U, v8::Integer::New(GetIsolate(), tree_id));
   v8::Local<v8::Array> nodes(v8::Array::New(GetIsolate(), ids.size()));
   args->Set(1U, nodes);
   for (size_t i = 0; i < ids.size(); ++i)
     nodes->Set(i, v8::Integer::New(GetIsolate(), ids[i]));
   context()->DispatchEvent("automationInternal.onNodesRemoved", args);
 }
 
 }  // namespace extensions