Thread ui opacity animations

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index 119a1cfa868390103209691c432da434f32c665f..a777e32caf5976da804d0c585124b3adf2b241e5 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -108,6 +108,7 @@ Layer::~Layer() {
     layer_mask_back_link_->SetMaskLayer(NULL);
   for (size_t i = 0; i < children_.size(); ++i)
     children_[i]->parent_ = NULL;
+  cc_layer_->removeLayerAnimationEventObserver(this);
   cc_layer_->removeFromParent();
 }
 
@@ -430,7 +431,9 @@ void Layer::SetExternalTexture(Texture* texture) {
       DCHECK(parent_->cc_layer_);
       parent_->cc_layer_->replaceChild(cc_layer_, new_layer);
     }
+    cc_layer_->removeLayerAnimationEventObserver(this);
     cc_layer_= new_layer;
+    cc_layer_->addLayerAnimationEventObserver(this);
     cc_layer_is_accelerated_ = layer_updated_externally_;
     for (size_t i = 0; i < children_.size(); ++i) {
       DCHECK(children_[i]->cc_layer_);
@@ -550,6 +553,11 @@ void Layer::SetForceRenderSurface(bool force) {
   cc_layer_->setForceRenderSurface(force_render_surface_);
 }
 
+void Layer::OnAnimationStarted(const cc::AnimationEvent& event) {
+  if (animator_)
+    animator_->OnThreadedAnimationStarted(event);
+}
+
 void Layer::StackRelativeTo(Layer* child, Layer* other, bool above) {
   DCHECK_NE(child, other);
   DCHECK_EQ(this, child->parent());
@@ -741,6 +749,16 @@ SkColor Layer::GetColorForAnimation() const {
       solid_color_layer_->backgroundColor() : SK_ColorBLACK;
 }
 
+void Layer::AddThreadedAnimation(scoped_ptr<cc::Animation> animation) {
+  DCHECK(cc_layer_);
+  cc_layer_->addAnimation(animation.Pass());
+}
+
+void Layer::RemoveThreadedAnimation(int animation_id) {
+  DCHECK(cc_layer_);
+  cc_layer_->removeAnimation(animation_id);
+}
+
 void Layer::CreateWebLayer() {
   if (type_ == LAYER_SOLID_COLOR) {
     solid_color_layer_ = cc::SolidColorLayer::create();
@@ -753,6 +771,7 @@ void Layer::CreateWebLayer() {
   cc_layer_->setAnchorPoint(gfx::PointF());
   cc_layer_->setContentsOpaque(true);
   cc_layer_->setIsDrawable(type_ != LAYER_NOT_DRAWN);
+  cc_layer_->addLayerAnimationEventObserver(this);
 }
 
 void Layer::RecomputeTransform() {