Added dummy definition for CanPartialSwap() in VulkanRenderer class

cc/output/vulkan_renderer.h

 // Copyright (c) 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 CC_OUTPUT_VULKAN_RENDERER_H_
 #define CC_OUTPUT_VULKAN_RENDERER_H_
 
 #include "cc/base/cc_export.h"
 #include "cc/output/direct_renderer.h"
 
 namespace cc {
 
 class TextureMailboxDeleter;
 
 class CC_EXPORT VulkanRenderer : public DirectRenderer {
  public:
   VulkanRenderer(const RendererSettings* settings,
                  OutputSurface* output_surface,
                  ResourceProvider* resource_provider,
                  TextureMailboxDeleter* texture_mailbox_deleter,
                  int highp_threshold_min);
   ~VulkanRenderer() override;
 
   // Implementation of public DirectRenderer functions.
   void SwapBuffers(const CompositorFrameMetadata& metadata) override;
   void ReceiveSwapBuffersAck(const CompositorFrameAck& ack) override;
+  bool CanPartialSwap() override;
 
  protected:
   // Implementations of protected Renderer functions.
   void DidChangeVisibility() override;
 
   // Implementations of protected DirectRenderer functions.
   void BindFramebufferToOutputSurface(DrawingFrame* frame) override;
   bool BindFramebufferToTexture(DrawingFrame* frame,
                                 const ScopedResource* resource) override;
   void SetScissorTestRect(const gfx::Rect& scissor_rect) override;
@@ skipping 15 matching lines @@
       DrawingFrame* frame,
       std::unique_ptr<CopyOutputRequest> request) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(VulkanRenderer);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_VULKAN_RENDERER_H_