Use void* again for PlatformFence

tools/gpu/vk/VkTestContext.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "VkTestContext.h"
 
 #ifdef SK_VULKAN
@@ skipping 85 matching lines @@
 private:
     sk_sp<const GrVkInterface>  fVk;
     VkDevice                    fDevice;
     VkQueue                     fQueue;
     VkCommandPool               fCommandPool;
     VkCommandBuffer             fCommandBuffer;
     SkDEBUGCODE(mutable int     fUnfinishedSyncs;)
     typedef sk_gpu_test::FenceSync INHERITED;
 };
 
+GR_STATIC_ASSERT(sizeof(VkFence) <= sizeof(sk_gpu_test::PlatformFence));
+
 // TODO: Implement swap buffers and finish
 class VkTestContextImpl : public sk_gpu_test::VkTestContext {
 public:
     static VkTestContext* Create() {
         sk_sp<const GrVkBackendContext> backendContext(GrVkBackendContext::Create());
         if (!backendContext) {
             return nullptr;
         }
         return new VkTestContextImpl(std::move(backendContext));
     }
@@ skipping 25 matching lines @@
 
     typedef sk_gpu_test::VkTestContext INHERITED;
 };
 }  // anonymous namespace
 
 namespace sk_gpu_test {
 VkTestContext* CreatePlatformVkTestContext() { return VkTestContextImpl::Create(); }
 }  // namespace sk_gpu_test
 
 #endif