Fix partial swap support

content/common/gpu/client/context_provider_command_buffer.cc

 // Copyright (c) 2013 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/common/gpu/client/context_provider_command_buffer.h"
 
 #include <set>
 #include <vector>
 
 #include "base/callback_helpers.h"
@@ skipping 247 matching lines @@
   caps.fast_npot_mo8_textures =
       extension_set.count("GL_CHROMIUM_fast_NPOT_MO8_textures") > 0;
 
   caps.egl_image_external =
       extension_set.count("GL_OES_EGL_image_external") > 0;
 
   caps.texture_format_bgra8888 =
       extension_set.count("GL_EXT_texture_format_BGRA8888") > 0;
   caps.texture_rectangle = extension_set.count("GL_ARB_texture_rectangle") > 0;
 
+  caps.post_sub_buffer = extension_set.count("GL_CHROMIUM_post_sub_buffer") > 0;
+
   // TODO(jamesr): This is unconditionally true on mac, no need to test for it
   // at runtime.
   caps.iosurface = extension_set.count("GL_CHROMIUM_iosurface") > 0;
 
   caps.texture_usage = extension_set.count("GL_ANGLE_texture_usage") > 0;
   caps.texture_storage = extension_set.count("GL_EXT_texture_storage") > 0;
 
   caps.discard_framebuffer =
       extension_set.count("GL_EXT_discard_framebuffer") > 0;
   size_t mapped_memory_limit = context3d_->GetMappedMemoryLimit();
@@ skipping 30 matching lines @@
 
 void ContextProviderCommandBuffer::SetMemoryPolicyChangedCallback(
     const MemoryPolicyChangedCallback& memory_policy_changed_callback) {
   DCHECK(context_thread_checker_.CalledOnValidThread());
   DCHECK(memory_policy_changed_callback_.is_null() ||
          memory_policy_changed_callback.is_null());
   memory_policy_changed_callback_ = memory_policy_changed_callback;
 }
 
 }  // namespace content