Recycle small uniform buffers.

src/gpu/vk/GrVkBuffer.h

Index: src/gpu/vk/GrVkBuffer.h
diff --git a/src/gpu/vk/GrVkBuffer.h b/src/gpu/vk/GrVkBuffer.h
index 232de176ce3eca9b672f55f5eee8e9d046a02363..b400e09916f4580587d29097250e199daed8f30b 100644
--- a/src/gpu/vk/GrVkBuffer.h
+++ b/src/gpu/vk/GrVkBuffer.h
@@ -53,7 +53,7 @@ protected:
         bool        fDynamic;
     };
 
-    class Resource : public GrVkResource {
+    class Resource : public GrVkRecycledResource {
     public:
         Resource(VkBuffer buf, const GrVkAlloc& alloc, Type type)
             : INHERITED(), fBuffer(buf), fAlloc(alloc), fType(type) {}
@@ -70,7 +70,9 @@ protected:
     private:
         void freeGPUData(const GrVkGpu* gpu) const override;
 
-        typedef GrVkResource INHERITED;
+        void onRecycle(GrVkGpu* gpu) const override { this->unref(gpu); }
+
+        typedef GrVkRecycledResource INHERITED;
     };
 
     // convenience routine for raw buffer creation