Document SkSurface::MakeRaster's memory initialization

src/image/SkSurface_Raster.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 187 matching lines @@
 
     SkAutoTUnref<SkPixelRef> pr(SkMallocPixelRef::NewZeroed(info, rowBytes, nullptr));
     if (nullptr == pr.get()) {
         return nullptr;
     }
     if (rowBytes) {
         SkASSERT(pr->rowBytes() == rowBytes);
     }
     return sk_make_sp<SkSurface_Raster>(pr, props);
 }
-
-sk_sp<SkSurface> SkSurface::MakeRaster(const SkImageInfo& info, const SkSurfaceProps* props) {
-    return MakeRaster(info, 0, props);
-}