Fix data race in RenderThreadImplBrowserTest

content/renderer/render_thread_impl.h

 // 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.
 
 #ifndef CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 468 matching lines @@
 
   mojom::StoragePartitionService* GetStoragePartitionService();
 
   // ChildMemoryCoordinatorDelegate implementation.
   void OnTrimMemoryImmediately() override;
 
  protected:
   RenderThreadImpl(
       const InProcessChildThreadParams& params,
       std::unique_ptr<blink::scheduler::RendererScheduler> scheduler,
-      scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
+      const scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
   RenderThreadImpl(
       std::unique_ptr<base::MessageLoop> main_message_loop,
       std::unique_ptr<blink::scheduler::RendererScheduler> scheduler);
 
  private:
   // IPC::Listener
   void OnChannelError() override;
 
   // ChildThread
   bool OnControlMessageReceived(const IPC::Message& msg) override;
@@ skipping 10 matching lines @@
       size_t size) override;
 
   // Purges memory and suspends the renderer.
   void SuspendRenderer();
 
   // base::MemoryCoordinatorClient implementation:
   void OnMemoryStateChange(base::MemoryState state) override;
 
   void ClearMemory();
 
-  void Init(scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
+  void Init(
+      const scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
 
   void InitializeCompositorThread();
 
   void InitializeWebKit(
-      scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
+      const scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
 
   void OnTransferBitmap(const SkBitmap& bitmap, int resource_id);
   void OnGetAccessibilityTree();
 
   // mojom::Renderer:
   void CreateView(mojom::CreateViewParamsPtr params) override;
   void CreateFrame(mojom::CreateFrameParamsPtr params) override;
   void CreateFrameProxy(int32_t routing_id,
                         int32_t render_view_routing_id,
                         int32_t opener_routing_id,
@@ skipping 232 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 #if defined(COMPILER_MSVC)
 #pragma warning(pop)
 #endif
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_