Revert of Move tracing namespace from base::debug to base::trace_event.

cc/quads/shared_quad_state.h

 // Copyright 2012 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_QUADS_SHARED_QUAD_STATE_H_
 #define CC_QUADS_SHARED_QUAD_STATE_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/transform.h"
 
 namespace base {
-namespace trace_event {
+namespace debug {
 class TracedValue;
 }
 class Value;
-
-// 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::TracedValue;
 }
-}  // namespace base
 
 namespace cc {
 
 // SharedQuadState holds a set of properties that are common across multiple
 // DrawQuads. It's purely an optimization - the properties behave in exactly the
 // same way as if they were replicated on each DrawQuad. A given SharedQuadState
 // can only be shared by DrawQuads that are adjacent in their RenderPass'
 // QuadList.
 class CC_EXPORT SharedQuadState {
  public:
@@ skipping 22 matching lines @@
   gfx::Rect clip_rect;
   bool is_clipped;
   float opacity;
   SkXfermode::Mode blend_mode;
   int sorting_context_id;
 };
 
 }  // namespace cc
 
 #endif  // CC_QUADS_SHARED_QUAD_STATE_H_