Consolidate GPU buffer implementations

src/gpu/vk/GrVkGpu.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrVkGpu.h"
 
 #include "GrContextOptions.h"
@@ skipping 371 matching lines @@
 
     // Release old command buffer and create a new one
     fCurrentCmdBuffer->unref(this);
     fCurrentCmdBuffer = fResourceProvider.createCommandBuffer();
     SkASSERT(fCurrentCmdBuffer);
 
     fCurrentCmdBuffer->begin(this);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
-GrVertexBuffer* GrVkGpu::onCreateVertexBuffer(size_t size, bool dynamic) {
+GrBuffer* GrVkGpu::onCreateVertexBuffer(size_t size, bool dynamic) {
     return GrVkVertexBuffer::Create(this, size, dynamic);
 }
 
-GrIndexBuffer* GrVkGpu::onCreateIndexBuffer(size_t size, bool dynamic) {
+GrBuffer* GrVkGpu::onCreateIndexBuffer(size_t size, bool dynamic) {
     return GrVkIndexBuffer::Create(this, size, dynamic);
 }
 
 GrTransferBuffer* GrVkGpu::onCreateTransferBuffer(size_t size, TransferType type) {
     GrVkBuffer::Type bufferType = kCpuToGpu_TransferType ? GrVkBuffer::kCopyRead_Type 
                                                          : GrVkBuffer::kCopyWrite_Type;
     return GrVkTransferBuffer::Create(this, size, bufferType);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 1254 matching lines @@
     int set_a_break_pt_here = 9;
     aglSwapBuffers(aglGetCurrentContext());
 #elif defined(SK_BUILD_FOR_WIN32)
     SwapBuf();
     int set_a_break_pt_here = 9;
     SwapBuf();
 #endif
 #endif
 }