Cleanup namespace usage in platform/fonts/.

Source/platform/fonts/FontFeatureSettings.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 25 matching lines @@
 
 bool FontFeature::operator==(const FontFeature& other)
 {
     return m_tag == other.m_tag && m_value == other.m_value;
 }
 
 FontFeatureSettings::FontFeatureSettings()
 {
 }
 
-}
+} // namespace blink