GPU: Add trace for real SwapBuffers.

ui/gl/gl_surface_wgl.cc

 // Copyright (c) 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.
 
 #include "ui/gl/gl_surface_wgl.h"
 
+#include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_gl_api_implementation.h"
 #include "ui/gl/gl_wgl_api_implementation.h"
 
 namespace gfx {
 
 namespace {
 const PIXELFORMATDESCRIPTOR kPixelFormatDescriptor = {
@@ skipping 243 matching lines @@
 
   child_window_ = NULL;
   device_context_ = NULL;
 }
 
 bool NativeViewGLSurfaceWGL::IsOffscreen() {
   return false;
 }
 
 bool NativeViewGLSurfaceWGL::SwapBuffers() {
+  TRACE_EVENT2("gpu", "NativeViewGLSurfaceWGL:RealSwapBuffers",
+      "width", GetSize().width(),
+      "height", GetSize().height());
+
   // Resize the child window to match the parent before swapping. Do not repaint
   // it as it moves.
   RECT rect;
   if (!GetClientRect(window_, &rect))
     return false;
   if (!MoveWindow(child_window_,
                   0, 0,
                   rect.right - rect.left,
                   rect.bottom - rect.top,
                   FALSE)) {
@@ skipping 79 matching lines @@
 
 gfx::Size PbufferGLSurfaceWGL::GetSize() {
   return size_;
 }
 
 void* PbufferGLSurfaceWGL::GetHandle() {
   return device_context_;
 }
 
 }  // namespace gfx