Cleanup namespace usage in public/platform/Web[A-M]*.h.

public/platform/WebFileSystemCallbacks.h

Index: public/platform/WebFileSystemCallbacks.h
diff --git a/public/platform/WebFileSystemCallbacks.h b/public/platform/WebFileSystemCallbacks.h
index a0b59eb37a85f5c553c4a944f68105cc971d22af..e53e87c4410628423b7039fd389ee735dd5bb622 100644
--- a/public/platform/WebFileSystemCallbacks.h
+++ b/public/platform/WebFileSystemCallbacks.h
@@ -38,18 +38,16 @@
 #include "WebPrivatePtr.h"
 #include "WebVector.h"
 
-namespace blink {
-class AsyncFileSystemCallbacks;
-}
 namespace WTF { template <typename T> class PassOwnPtr; }
 
 namespace blink {
 
-struct WebFileInfo;
+class AsyncFileSystemCallbacks;
 class WebFileWriter;
 class WebString;
 class WebURL;
 class WebFileSystemCallbacksPrivate;
+struct WebFileInfo;
 
 class WebFileSystemCallbacks {
 public:
@@ -66,7 +64,7 @@ public:
     BLINK_PLATFORM_EXPORT void assign(const WebFileSystemCallbacks&);
 
 #if INSIDE_BLINK
-    BLINK_PLATFORM_EXPORT WebFileSystemCallbacks(const WTF::PassOwnPtr<blink::AsyncFileSystemCallbacks>&);
+    BLINK_PLATFORM_EXPORT WebFileSystemCallbacks(const WTF::PassOwnPtr<AsyncFileSystemCallbacks>&);
 #endif
 
     // Callback for WebFileSystem's various operations that don't require