[WIP] Attempt to move everything cssom into a cssom namespace

third_party/WebKit/Source/core/css/cssom/MutableStylePropertyMap.h

 // Copyright 2016 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.
 
 #ifndef MutableStylePropertyMap_h
 #define MutableStylePropertyMap_h
 
 #include "core/css/cssom/StylePropertyMap.h"
 
 namespace blink {
+namespace cssom {
 
 class CORE_EXPORT MutableStylePropertyMap : public StylePropertyMap {
     WTF_MAKE_NONCOPYABLE(MutableStylePropertyMap);
 protected:
     MutableStylePropertyMap() = default;
 };
 
+} // namespace cssom
 } // namespace blink
 
+
 #endif