Remove all traces of compositing reasons from cc

cc/layers/layer.cc

Index: cc/layers/layer.cc
diff --git a/cc/layers/layer.cc b/cc/layers/layer.cc
index f7682fd912fd8dca3642345973bb93abec30e2df..7110dc70812c7987694b81fb8549345cc0c88d2d 100644
--- a/cc/layers/layer.cc
+++ b/cc/layers/layer.cc
@@ -57,7 +57,6 @@ Layer::Layer()
       force_render_surface_(false),
       anchor_point_(0.5f, 0.5f),
       background_color_(0),
-      compositing_reasons_(kCompositingReasonUnknown),
       opacity_(1.f),
       blend_mode_(SkXfermode::kSrcOver_Mode),
       anchor_point_z_(0.f),
@@ -883,7 +882,6 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
     layer->SetDebugName(std::string());
   }
 
-  layer->SetCompositingReasons(compositing_reasons_);
   layer->SetDoubleSided(double_sided_);
   layer->SetDrawCheckerboardForMissingTiles(
       draw_checkerboard_for_missing_tiles_);
@@ -1046,11 +1044,6 @@ scoped_refptr<base::debug::ConvertableToTraceFormat> Layer::TakeDebugInfo() {
     return NULL;
 }
 
-
-void Layer::SetCompositingReasons(CompositingReasons reasons) {
-  compositing_reasons_ = reasons;
-}
-
 void Layer::CreateRenderSurface() {
   DCHECK(!draw_properties_.render_surface);
   draw_properties_.render_surface = make_scoped_ptr(new RenderSurface(this));