Create and use BlinkInterfaceProvider WeakPtrs on the same thread

content/renderer/mojo/blink_interface_provider_impl.h

 // Copyright 2016 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_MOJO_BLINK_INTERFACE_PROVIDER_IMPL_H_
 #define CONTENT_RENDERER_MOJO_BLINK_INTERFACE_PROVIDER_IMPL_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 20 matching lines @@
 
   // blink::InterfaceProvider override.
   void getInterface(const char* name,
                     mojo::ScopedMessagePipeHandle handle) override;
 
  private:
   const base::WeakPtr<shell::InterfaceProvider> remote_interfaces_;
 
   scoped_refptr<base::SingleThreadTaskRunner> main_thread_task_runner_;
 
+  // Should only be accessed by Web Worker threads that are using the
+  // blink::Platform-level interface provider.
+  base::WeakPtr<BlinkInterfaceProviderImpl> weak_ptr_;
   base::WeakPtrFactory<BlinkInterfaceProviderImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BlinkInterfaceProviderImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MOJO_BLINK_INTERFACE_PROVIDER_IMPL_H_