Add a hide_layer_and_subtree() flag to cc::Layer

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index 09009eae4bea691e2d975b00da9ec28c3a4b71df..1c0fc68c87b29b640a3059b22e3fd12f173d715c 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -47,7 +47,6 @@ Layer::Layer()
       compositor_(NULL),
       parent_(NULL),
       visible_(true),
-      is_drawn_(true),
       force_render_surface_(false),
       fills_bounds_opaquely_(true),
       layer_updated_externally_(false),
@@ -72,7 +71,6 @@ Layer::Layer(LayerType type)
       compositor_(NULL),
       parent_(NULL),
       visible_(true),
-      is_drawn_(true),
       force_render_surface_(false),
       fills_bounds_opaquely_(true),
       layer_updated_externally_(false),
@@ -142,7 +140,6 @@ void Layer::Add(Layer* child) {
   children_.push_back(child);
   cc_layer_->AddChild(child->cc_layer_);
   child->OnDeviceScaleFactorChanged(device_scale_factor_);
-  child->UpdateIsDrawn();
   if (GetCompositor())
     child->SendPendingThreadedAnimations();
 }
@@ -370,21 +367,10 @@ bool Layer::GetTargetVisibility() const {
 }
 
 bool Layer::IsDrawn() const {
-  return is_drawn_;
-}
-
-void Layer::UpdateIsDrawn() {
-  bool updated_is_drawn = visible_ && (!parent_ || parent_->IsDrawn());
-
-  if (updated_is_drawn == is_drawn_)
-    return;
-
-  is_drawn_ = updated_is_drawn;
-  cc_layer_->SetIsDrawable(is_drawn_ && type_ != LAYER_NOT_DRAWN);
-
-  for (size_t i = 0; i < children_.size(); ++i) {
-    children_[i]->UpdateIsDrawn();
-  }
+  const Layer* layer = this;
+  while (layer && layer->visible_)
+    layer = layer->parent_;
+  return layer == NULL;
 }
 
 bool Layer::ShouldDraw() const {
@@ -478,7 +464,8 @@ void Layer::SwitchToLayer(scoped_refptr<cc::Layer> new_layer) {
   cc_layer_->SetAnchorPoint(gfx::PointF());
   cc_layer_->SetContentsOpaque(fills_bounds_opaquely_);
   cc_layer_->SetForceRenderSurface(force_render_surface_);
-  cc_layer_->SetIsDrawable(IsDrawn());
+  cc_layer_->SetIsDrawable(type_ != LAYER_NOT_DRAWN);
+  cc_layer_->SetHideLayerAndSubtree(!visible_);
 }
 
 void Layer::SwitchCCLayerForTest() {
@@ -773,7 +760,7 @@ void Layer::SetVisibilityImmediately(bool visible) {
     return;
 
   visible_ = visible;
-  UpdateIsDrawn();
+  cc_layer_->SetHideLayerAndSubtree(!visible_);
 }
 
 void Layer::SetBrightnessImmediately(float brightness) {