Keeping track of descendants that draw content instead of recalcualting

cc/layers/texture_layer.cc

 // Copyright 2010 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 "cc/layers/texture_layer.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/synchronization/lock.h"
@@ skipping 27 matching lines @@
 }
 
 TextureLayer::~TextureLayer() {
 }
 
 void TextureLayer::ClearClient() {
   if (rate_limit_context_ && client_ && layer_tree_host())
     layer_tree_host()->StopRateLimiter();
   client_ = NULL;
   ClearTexture();
+  UpdateDrawsContent(true);
 }
 
 void TextureLayer::ClearTexture() {
   SetTextureMailbox(TextureMailbox(), scoped_ptr<SingleReleaseCallback>());
 }
 
 scoped_ptr<LayerImpl> TextureLayer::CreateLayerImpl(LayerTreeImpl* tree_impl) {
   return TextureLayerImpl::Create(tree_impl, id()).PassAs<LayerImpl>();
 }
 
@@ skipping 71 matching lines @@
   } else {
     holder_ref_.reset();
   }
   needs_set_mailbox_ = true;
   // If we are within a commit, no need to do it again immediately after.
   if (requires_commit)
     SetNeedsCommit();
   else
     SetNeedsPushProperties();
 
+  UpdateDrawsContent(true);
   // The active frame needs to be replaced and the mailbox returned before the
   // commit is called complete.
   SetNextCommitWaitsForActivation();
 }
 
 void TextureLayer::SetTextureMailbox(
     const TextureMailbox& mailbox,
     scoped_ptr<SingleReleaseCallback> release_callback) {
   bool requires_commit = true;
   bool allow_mailbox_reuse = false;
@@ skipping 42 matching lines @@
   // time we push.
   if (!host && holder_ref_) {
     needs_set_mailbox_ = true;
     // The active frame needs to be replaced and the mailbox returned before the
     // commit is called complete.
     SetNextCommitWaitsForActivation();
   }
   Layer::SetLayerTreeHost(host);
 }
 
-bool TextureLayer::DrawsContent() const {
-  return (client_ || holder_ref_) && Layer::DrawsContent();
+void TextureLayer::UpdateDrawsContent(bool draws_content) {
+  Layer::UpdateDrawsContent(draws_content && (client_ || holder_ref_));
 }
 
 bool TextureLayer::Update(ResourceUpdateQueue* queue,
                           const OcclusionTracker<Layer>* occlusion) {
   bool updated = Layer::Update(queue, occlusion);
   if (client_) {
     TextureMailbox mailbox;
     scoped_ptr<SingleReleaseCallback> release_callback;
     if (client_->PrepareTextureMailbox(
             &mailbox,
@@ skipping 114 matching lines @@
 
 void TextureLayer::TextureMailboxHolder::ReturnAndReleaseOnImplThread(
     uint32 sync_point,
     bool is_lost) {
   Return(sync_point, is_lost);
   message_loop_->PostTask(
       FROM_HERE, base::Bind(&TextureMailboxHolder::InternalRelease, this));
 }
 
 }  // namespace cc