Added the Vulkan Context Provider implementation.

cc/output/output_surface.h

 // Copyright 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 CC_OUTPUT_OUTPUT_SURFACE_H_
 #define CC_OUTPUT_OUTPUT_SURFACE_H_
 
 #include <deque>
 #include <memory>
 
@@ skipping 42 matching lines @@
                 scoped_refptr<ContextProvider> worker_context_provider,
 #if defined(ENABLE_VULKAN)
                 scoped_refptr<VulkanContextProvider> vulkan_context_provider,
 #endif
                 std::unique_ptr<SoftwareOutputDevice> software_device);
   OutputSurface(scoped_refptr<ContextProvider> context_provider,
                 scoped_refptr<ContextProvider> worker_context_provider);
   explicit OutputSurface(scoped_refptr<ContextProvider> context_provider);
 #if defined(ENABLE_VULKAN)
   explicit OutputSurface(
-      scoped_refptr<VulkanContextProvider> vulkan_context_provider);
+      scoped_refptr<VulkanContextProvider> vulkan_context_provider,
+      bool use_vulkan);

[piman, 2016/04/19 01:36:42]

What's the reason for use_vulkan, it's not used except for a DCHECK?

[David Yen, 2016/04/19 22:20:27]

This was so I could override the constructor, it conflicts with the
OutputSurface(ContextProvider) constructor because it is the base class.

Perhaps a better way is to just call the constructor with all the arguments and
pass in nullptr for the other arguments.

[piman, 2016/04/19 23:29:57]

I think you're running into a scoped_refptr limitation, should be fixed with
https://codereview.chromium.org/1904603002/

 #endif
   explicit OutputSurface(std::unique_ptr<SoftwareOutputDevice> software_device);
 
   OutputSurface(scoped_refptr<ContextProvider> context_provider,
                 std::unique_ptr<SoftwareOutputDevice> software_device);
 
   ~OutputSurface() override;
 
   struct Capabilities {
     Capabilities()
@@ skipping 134 matching lines @@
   bool external_stencil_test_enabled_;
 
   base::WeakPtrFactory<OutputSurface> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OutputSurface);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_OUTPUT_SURFACE_H_