Update the nine patch layer to use UI resources

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 27659e054bea869e8bcc1940036e2f5d82fead9b..23e092975c0b24af439756f56b3c7134d05b4484 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -61,7 +61,7 @@ RendererCapabilities::RendererCapabilities()
 RendererCapabilities::~RendererCapabilities() {}
 
 UIResourceRequest::UIResourceRequest()
-    : type(UIResourceInvalidRequest), id(0), bitmap(NULL) {}
+    : type(UIResourceInvalidRequest), id(0) {}
 
 UIResourceRequest::~UIResourceRequest() {}
 
@@ -1123,53 +1123,70 @@ void LayerTreeHost::AnimateLayers(base::TimeTicks time) {
 UIResourceId LayerTreeHost::CreateUIResource(UIResourceClient* client) {
   DCHECK(client);
 
-  UIResourceRequest request;
-  bool resource_lost = false;
-  request.type = UIResourceRequest::UIResourceCreate;
-  request.id = next_ui_resource_id_++;
+  UIResourceId next_id = next_ui_resource_id_++;
 
-  DCHECK(ui_resource_client_map_.find(request.id) ==
+  DCHECK(ui_resource_client_map_.find(next_id) ==
          ui_resource_client_map_.end());
 
-  request.bitmap = client->GetBitmap(request.id, resource_lost);
+  bool resource_lost = false;
+  UIResourceRequest request;
+  request.type = UIResourceRequest::UIResourceCreate;
+  request.id = next_id;
+  request.bitmap = client->GetBitmap(next_id, resource_lost);
   ui_resource_request_queue_.push_back(request);
-  ui_resource_client_map_[request.id] = client;
+
+  UIResourceClientData data;
+  data.client = client;
+  data.size = request.bitmap.GetSize();
+
+  ui_resource_client_map_[request.id] = data;
   return request.id;
 }
 
 // Deletes a UI resource.  May safely be called more than once.
 void LayerTreeHost::DeleteUIResource(UIResourceId uid) {
-  UIResourceClientMap::iterator iter = ui_resource_client_map_.find(uid);
-  if (iter == ui_resource_client_map_.end())
+  UIResourceClientMap::iterator it = ui_resource_client_map_.find(uid);
+  if (it == ui_resource_client_map_.end())
     return;
 
   UIResourceRequest request;
   request.type = UIResourceRequest::UIResourceDelete;
   request.id = uid;
   ui_resource_request_queue_.push_back(request);
-  ui_resource_client_map_.erase(uid);
+  ui_resource_client_map_.erase(it);
+}
+
+// Returns the size of a resource given its id.
+gfx::Size LayerTreeHost::GetUIResourceSize(UIResourceId uid) const {
+  UIResourceClientMap::const_iterator it = ui_resource_client_map_.find(uid);
+  if (it == ui_resource_client_map_.end())
+    return gfx::Size();
+
+  const UIResourceClientData& data = it->second;
+  return data.size;
 }
 
 void LayerTreeHost::UIResourceLost(UIResourceId uid) {
-  UIResourceClientMap::iterator iter = ui_resource_client_map_.find(uid);
-  if (iter == ui_resource_client_map_.end())
+  UIResourceClientMap::iterator it = ui_resource_client_map_.find(uid);
+  if (it == ui_resource_client_map_.end())
     return;
 
-  UIResourceRequest request;
+  UIResourceClientData data = it->second;
   bool resource_lost = true;
+  UIResourceRequest request;
   request.type = UIResourceRequest::UIResourceCreate;
   request.id = uid;
-  request.bitmap = iter->second->GetBitmap(uid, resource_lost);
-  DCHECK(request.bitmap.get());
+  request.bitmap = data.client->GetBitmap(uid, resource_lost);
+
   ui_resource_request_queue_.push_back(request);
 }
 
 void LayerTreeHost::DidLoseUIResources() {
   // When output surface is lost, we need to recreate the resource.
-  for (UIResourceClientMap::iterator iter = ui_resource_client_map_.begin();
-       iter != ui_resource_client_map_.end();
-       ++iter) {
-    UIResourceLost(iter->first);
+  for (UIResourceClientMap::iterator it = ui_resource_client_map_.begin();
+       it != ui_resource_client_map_.end();
+       ++it) {
+    UIResourceLost(it->first);
   }
 }