Consolidate OutputSurface constructors into GL vs Vulkan.

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 28 matching lines @@
 
 // Represents the output surface for a compositor. The compositor owns
 // and manages its destruction. Its lifetime is:
 //   1. Created on the main thread by the LayerTreeHost through its client.
 //   2. Passed to the compositor thread and bound to a client via BindToClient.
 //      From here on, it will only be used on the compositor thread.
 //   3. If the 3D context is lost, then the compositor will delete the output
 //      surface (on the compositor thread) and go back to step 1.
 class CC_EXPORT OutputSurface : public base::trace_event::MemoryDumpProvider {
  public:
-  OutputSurface(scoped_refptr<ContextProvider> context_provider,
-                scoped_refptr<ContextProvider> worker_context_provider,
-                scoped_refptr<VulkanContextProvider> vulkan_context_provider,
-                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);
-  explicit OutputSurface(std::unique_ptr<SoftwareOutputDevice> software_device);
+  // Constructor for GL-based and/or software compositing.
+  explicit OutputSurface(scoped_refptr<ContextProvider> context_provider,

[piman, 2016/05/23 23:12:38]

nit: no need for explicit?

[danakj, 2016/05/23 23:16:01]

Kinda but actually I think you can hit multi-param constructors implicitly now,
due to {} initialization. explicit on everything seems good.

+                         scoped_refptr<ContextProvider> worker_context_provider,
+                         std::unique_ptr<SoftwareOutputDevice> software_device);
 
-  OutputSurface(scoped_refptr<ContextProvider> context_provider,
-                std::unique_ptr<SoftwareOutputDevice> software_device);
+  // Constructor for Vulkan-based compositing.
+  explicit OutputSurface(
+      scoped_refptr<VulkanContextProvider> vulkan_context_provider);
 
   ~OutputSurface() override;
 
   struct Capabilities {
     Capabilities()
         : delegated_rendering(false),
           max_frames_pending(1),
           adjust_deadline_for_parent(true),
           uses_default_gl_framebuffer(true),
           flipped_output_surface(false),
@@ skipping 95 matching lines @@
   virtual void SetWorkerContextShouldAggressivelyFreeResources(bool is_visible);
 
   // If this returns true, then the surface will not attempt to draw.
   virtual bool SurfaceIsSuspendForRecycle() const;
 
   // base::trace_event::MemoryDumpProvider implementation.
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
                     base::trace_event::ProcessMemoryDump* pmd) override;
 
  protected:
-  OutputSurfaceClient* client_;
+  void PostSwapBuffersComplete();
 
-  void PostSwapBuffersComplete();
+  OutputSurfaceClient* client_ = nullptr;
 
   struct OutputSurface::Capabilities capabilities_;
   scoped_refptr<ContextProvider> context_provider_;
   scoped_refptr<ContextProvider> worker_context_provider_;
   scoped_refptr<VulkanContextProvider> vulkan_context_provider_;
   std::unique_ptr<SoftwareOutputDevice> software_device_;
   gfx::Size surface_size_;
-  float device_scale_factor_;
-  bool has_alpha_;
+  float device_scale_factor_ = -1;
+  bool has_alpha_ = true;
   base::ThreadChecker client_thread_checker_;
 
   void SetNeedsRedrawRect(const gfx::Rect& damage_rect);
   void ReclaimResources(const CompositorFrameAck* ack);
   void SetExternalStencilTest(bool enabled);
   void DetachFromClientInternal();
 
  private:
-  bool external_stencil_test_enabled_;
+  bool external_stencil_test_enabled_ = false;
 
   base::WeakPtrFactory<OutputSurface> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OutputSurface);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_OUTPUT_SURFACE_H_