Add GpuCommandBuffer support.

src/gpu/gl/GrGLGpu.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGLGpu_DEFINED
 #define GrGLGpu_DEFINED
 
@@ skipping 83 matching lines @@
 
     // Called by GrGLBuffer after its buffer object has been destroyed.
     void notifyBufferReleased(const GrGLBuffer*);
 
     const GrGLContext* glContextForTesting() const override {
         return &this->glContext();
     }
 
     void clearStencil(GrRenderTarget*) override;
 
+    GrGpuCommandBuffer* createCommandBuffer(const GrRenderTarget& target,
+                                            GrGpuCommandBuffer::LoadAndStoreOp colorOp,
+                                            GrColor colorClear,
+                                            GrGpuCommandBuffer::LoadAndStoreOp stencilOp,
+                                            GrColor stencilClear) override;
+
     void invalidateBoundRenderTarget() {
         fHWBoundRenderTargetUniqueID = SK_InvalidUniqueID;
     }
 
     GrStencilAttachment* createStencilAttachmentForRenderTarget(const GrRenderTarget* rt,
                                                                 int width,
                                                                 int height) override;
 
     GrBackendObject createTestingOnlyBackendTexture(void* pixels, int w, int h,
                                                     GrPixelConfig config) override;
@@ skipping 466 matching lines @@
     bool fHWPLSEnabled;
     bool fPLSHasBeenUsed;
 
     float fHWMinSampleShading;
 
     typedef GrGpu INHERITED;
     friend class GrGLPathRendering; // For accessing setTextureUnit.
 };
 
 #endif