Update from https://crrev.com/316786

cc/layers/layer.h

 // 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.
 
 #ifndef CC_LAYERS_LAYER_H_
 #define CC_LAYERS_LAYER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 29 matching lines @@
 #include "ui/gfx/transform.h"
 
 namespace gfx {
 class BoxF;
 }
 
 namespace base {
 namespace trace_event {
 class ConvertableToTraceFormat;
 }
-
-// TODO(ssid): remove these aliases after the tracing clients are moved to the
-// new trace_event namespace. See crbug.com/451032. ETA: March 2015
-namespace debug {
-using ::base::trace_event::ConvertableToTraceFormat;
 }
-}  // namespace base
 
 namespace cc {
 
 class Animation;
 class AnimationDelegate;
 struct AnimationEvent;
 class CopyOutputRequest;
 class LayerAnimationDelegate;
 class LayerAnimationEventObserver;
 class LayerClient;
@@ skipping 309 matching lines @@
   virtual void SavePaintProperties();
   // Returns true iff any resources were updated that need to be committed.
   virtual bool Update(ResourceUpdateQueue* queue,
                       const OcclusionTracker<Layer>* occlusion);
   virtual bool NeedMoreUpdates();
   virtual void SetIsMask(bool is_mask) {}
   virtual void ReduceMemoryUsage() {}
   virtual void OnOutputSurfaceCreated() {}
   virtual bool IsSuitableForGpuRasterization() const;
 
-  virtual scoped_refptr<base::debug::ConvertableToTraceFormat> TakeDebugInfo();
+  virtual scoped_refptr<base::trace_event::ConvertableToTraceFormat>
+  TakeDebugInfo();
 
   void SetLayerClient(LayerClient* client) { client_ = client; }
 
   virtual void PushPropertiesTo(LayerImpl* layer);
 
   void CreateRenderSurface();
   void ClearRenderSurface();
 
   void ClearRenderSurfaceLayerList();
 
@@ skipping 322 matching lines @@
 
   std::vector<FrameTimingRequest> frame_timing_requests_;
   bool frame_timing_requests_dirty_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_H_