Revert of Add Gr*Proxy classes

src/gpu/GrSurfaceProxy.cpp

Index: src/gpu/GrSurfaceProxy.cpp
diff --git a/src/gpu/GrSurfaceProxy.cpp b/src/gpu/GrSurfaceProxy.cpp
deleted file mode 100644
index b8b5d7510d40f5f9e0e39d1228b24e953019a630..0000000000000000000000000000000000000000
--- a/src/gpu/GrSurfaceProxy.cpp
+++ /dev/null
@@ -1,19 +0,0 @@
-/*
- * 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 "GrSurfaceProxy.h"
-
-#include "SkAtomics.h"
-
-uint32_t GrSurfaceProxy::CreateUniqueID() {
-    static int32_t gUniqueID = SK_InvalidUniqueID;
-    uint32_t id;
-    do {
-        id = static_cast<uint32_t>(sk_atomic_inc(&gUniqueID) + 1);
-    } while (id == SK_InvalidUniqueID);
-    return id;
-}