captureVisibleTab Extension API producing garbled PNG results

ui/gfx/codec/png_codec.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gfx/codec/png_codec.h"
 
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "ui/gfx/size.h"
 #include "ui/gfx/skia_util.h"
@@ skipping 750 matching lines @@
 // static
 bool PNGCodec::EncodeBGRASkBitmap(const SkBitmap& input,
                                   bool discard_transparency,
                                   std::vector<unsigned char>* output) {
   static const int bbp = 4;
 
   SkAutoLockPixels lock_input(input);
   if (input.empty())
     return false;
   DCHECK(input.bytesPerPixel() == bbp);
+  DCHECK(static_cast<int>(input.rowBytes()) >= input.width() * bbp);
 
   return Encode(reinterpret_cast<unsigned char*>(input.getAddr32(0, 0)),
                 FORMAT_SkBitmap, Size(input.width(), input.height()),
-                input.width() * bbp, discard_transparency,
+                static_cast<int>(input.rowBytes()), discard_transparency,
                 std::vector<Comment>(), output);
 }
 
 PNGCodec::Comment::Comment(const std::string& k, const std::string& t)
     : key(k), text(t) {
 }
 
 PNGCodec::Comment::~Comment() {
 }
 
 }  // namespace gfx