Use std::string instead of WTF::String / TextStream

cc/cc.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 0,
     'use_libcc_for_compositor%': 0,
     'cc_source_files': [
       'BitmapCanvasLayerTextureUpdater.cpp',
@@ skipping 231 matching lines @@
             'stubs/FloatRect.h',
             'stubs/FloatSize.h',
             'stubs/GraphicsContext3D.h',
             'stubs/GraphicsTypes3D.h',
             'stubs/IntPoint.h',
             'stubs/IntRect.h',
             'stubs/IntSize.h',
             'stubs/NotImplemented.h',
             'stubs/Region.h',
             'stubs/SkiaUtils.h',
-            'stubs/TextStream.h',
             'stubs/TilingData.h',
             'stubs/TraceEvent.h',
             'stubs/UnitBezier.h',
           ],
         }],
       ],
     },
   ],
 }