Cleanup namespace usage in Source/web/Web[I-Z]*.cpp

Source/web/WebImageCache.cpp

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "public/web/WebImageCache.h"
 
 #include "platform/graphics/ImageDecodingStore.h"
 
-using blink::ImageDecodingStore;
-
 namespace blink {
 
 void WebImageCache::setCacheLimitInBytes(size_t size)
 {
     ImageDecodingStore::instance()->setCacheLimitInBytes(size);
 }
 
 void WebImageCache::clear()
 {
     if (ImageDecodingStore::instance())
         ImageDecodingStore::instance()->clear();
 }
 
 size_t WebImageCache::memoryUsageInBytes()
 {
     return ImageDecodingStore::instance()->memoryUsageInBytes();
 }
 
 unsigned WebImageCache::cacheEntries()
 {
     return ImageDecodingStore::instance()->cacheEntries();
 }
 
 }  // namespace blink