Fix build error with XCode6/OSX 10.9 SDK

content/browser/renderer_host/compositing_iosurface_mac.mm

 // 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 "content/browser/renderer_host/compositing_iosurface_mac.h"
 
 #include <OpenGL/CGLIOSurface.h>
 #include <OpenGL/CGLRenderers.h>
 #include <OpenGL/OpenGL.h>
+#include <OpenGL/gl.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/threading/platform_thread.h"
 #include "content/browser/gpu/gpu_data_manager_impl.h"
 #include "content/browser/renderer_host/compositing_iosurface_context_mac.h"
@@ skipping 347 matching lines @@
 }
 
 // static
 base::LazyInstance<CompositingIOSurfaceMac::EvictionQueue>
     CompositingIOSurfaceMac::eviction_queue_;
 
 // static
 bool CompositingIOSurfaceMac::eviction_scheduled_ = false;
 
 }  // namespace content