Add fence support for TransferBuffers

tools/gpu/GrTest.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTest.h"
 
 #include "GrBatchAtlas.h"
@@ skipping 300 matching lines @@
     }
 
     GrGpuCommandBuffer* createCommandBuffer(GrRenderTarget* target,
                                             const GrGpuCommandBuffer::LoadAndStoreInfo&,
                                             const GrGpuCommandBuffer::LoadAndStoreInfo&) override {
         return nullptr;
     }
 
     void drawDebugWireRect(GrRenderTarget*, const SkIRect&, GrColor) override {}
 
+    GrFence SK_WARN_UNUSED_RESULT insertFence() const override { return 0; }
+    bool waitFence(GrFence, uint64_t) const override { return true; }
+    void deleteFence(GrFence) const override {}
+
 private:
     void onResetContext(uint32_t resetBits) override {}
 
     void xferBarrier(GrRenderTarget*, GrXferBarrierType) override {}
 
     GrTexture* onCreateTexture(const GrSurfaceDesc& desc, SkBudgeted budgeted,
                                const SkTArray<GrMipLevel>& texels) override {
         return nullptr;
     }
 
@@ skipping 74 matching lines @@
     SkASSERT(nullptr == fGpu);
     fGpu = new MockGpu(this, options);
     SkASSERT(fGpu);
     this->initCommon(options);
 
     // We delete these because we want to test the cache starting with zero resources. Also, none of
     // these objects are required for any of tests that use this context. TODO: make stop allocating
     // resources in the buffer pools.
     fDrawingManager->abandon();
 }