Add helper for creating a SkSurface from a client created texture.

src/image/SkSurface.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkSurface_Base.h"
 #include "SkImagePriv.h"
 #include "SkCanvas.h"
@@ skipping 170 matching lines @@
 
 SkSurface* SkSurface::NewRenderTargetDirect(GrRenderTarget*, const SkSurfaceProps*) {
     return NULL;
 }
 
 SkSurface* SkSurface::NewRenderTarget(GrContext*, Budgeted, const SkImageInfo&, int,
                                       const SkSurfaceProps*) {
     return NULL;
 }
 
+SkSurface* SkSurface::NewWrappedRenderTarget(GrContext*, GrBackendTextureDesc,
+                                             const SkSurfaceProps*) {
+    return NULL;
+}
 
 #endif