Re-land: cc: Implement shared worker contexts.

cc/test/test_context_provider.h

 // Copyright 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.
 
 #ifndef CC_TEST_TEST_CONTEXT_PROVIDER_H_
 #define CC_TEST_TEST_CONTEXT_PROVIDER_H_
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "cc/output/context_provider.h"
 #include "cc/test/test_context_support.h"
 #include "gpu/command_buffer/client/gles2_interface_stub.h"
 #include "skia/ext/refptr.h"
 
 namespace cc {
 class TestWebGraphicsContext3D;
 class TestGLES2Interface;
 
 class TestContextProvider : public ContextProvider {
  public:
   typedef base::Callback<scoped_ptr<TestWebGraphicsContext3D>(void)>
     CreateCallback;
 
   static scoped_refptr<TestContextProvider> Create();
+  // Creates a worker context provider that can be used on any thread. This is
+  // equivalent to: Create(); BindToCurrentThread(); SetupLock().
+  static scoped_refptr<TestContextProvider> CreateWorker();
   static scoped_refptr<TestContextProvider> Create(
       scoped_ptr<TestWebGraphicsContext3D> context);
 
   bool BindToCurrentThread() override;
   void DetachFromThread() override;
   Capabilities ContextCapabilities() override;
   gpu::gles2::GLES2Interface* ContextGL() override;
   gpu::ContextSupport* ContextSupport() override;
   class GrContext* GrContext() override;
   void InvalidateGrContext(uint32_t state) override;
@@ skipping 47 matching lines @@
 
   base::WeakPtrFactory<TestContextProvider> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TestContextProvider);
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_TEST_CONTEXT_PROVIDER_H_