Add GrVkRecycledResource subclass

src/gpu/vk/GrVkResource.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrVkResource_DEFINED
 #define GrVkResource_DEFINED
 
@@ skipping 173 matching lines @@
     }
 
     mutable int32_t fRefCnt;
 #ifdef SK_TRACE_VK_RESOURCES
     uint32_t fKey;
 #endif
 
     typedef SkNoncopyable INHERITED;
 };
 
+// This subclass allows for recycling
+class GrVkRecycledResource : public GrVkResource {
+public:
+    void recycle(GrVkGpu* gpu) const {
+        if (this->unique()) {
+            this->onRecycle(gpu);

[jvanverth1, 2016/07/20 14:08:47]

Why not put the unref in here?

[egdaniel, 2016/07/20 14:48:39]

Done.

+        }
+    }
+
+private:
+    virtual void onRecycle(GrVkGpu* gpu) const = 0;
+};
 
 #endif