blimp: Set up the CompositorDependencies for blimp in Chrome.

blimp/client/support/compositor/blimp_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 BLIMP_CLIENT_SUPPORT_COMPOSITOR_BLIMP_CONTEXT_PROVIDER_H_
 #define BLIMP_CLIENT_SUPPORT_COMPOSITOR_BLIMP_CONTEXT_PROVIDER_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 41 matching lines @@
   void OnLostContext();
 
   base::ThreadChecker main_thread_checker_;
   base::ThreadChecker context_thread_checker_;
 
   std::unique_ptr<gpu::GLInProcessContext> context_;
   std::unique_ptr<skia_bindings::GrContextForGLES2Interface> gr_context_;
 
   LostContextCallback lost_context_callback_;
 
+  base::Lock context_lock_;
+
   DISALLOW_COPY_AND_ASSIGN(BlimpContextProvider);
 };
 
 }  // namespace client
 }  // namespace blimp
 
 #endif  // BLIMP_CLIENT_SUPPORT_COMPOSITOR_BLIMP_CONTEXT_PROVIDER_H_