Remove unused features for in-process GL contexts.

android_webview/browser/aw_render_thread_context_provider.h

 // Copyright 2015 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 ANDROID_WEBVIEW_BROWSER_AW_RENDER_THREAD_CONTEXT_PROVIDER_H_
 #define ANDROID_WEBVIEW_BROWSER_AW_RENDER_THREAD_CONTEXT_PROVIDER_H_
 
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/macros.h"
-#include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "cc/output/context_provider.h"
 #include "gpu/command_buffer/service/in_process_command_buffer.h"
 #include "skia/ext/refptr.h"
 
 namespace gfx {
 class GLSurface;
 }
 
 namespace gpu {
@@ skipping 31 matching lines @@
 
   base::ThreadChecker main_thread_checker_;
 
   std::unique_ptr<gpu::GLInProcessContext> context_;
   skia::RefPtr<class GrContext> gr_context_;
 
   cc::ContextProvider::Capabilities capabilities_;
 
   LostContextCallback lost_context_callback_;
 
-  base::Lock context_lock_;
-
   DISALLOW_COPY_AND_ASSIGN(AwRenderThreadContextProvider);
 };
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_BROWSER_AW_RENDER_THREAD_CONTEXT_PROVIDER_H_