Cleanup namespace usage in public/web/Web[N-Z]*.h.

public/web/WebScopedUserGesture.h

Index: public/web/WebScopedUserGesture.h
diff --git a/public/web/WebScopedUserGesture.h b/public/web/WebScopedUserGesture.h
index d27374a81ef469db71fab402c35d9fe8055bb76d..a4e3903f3f4dc20439ba672f8492318d829aa197 100644
--- a/public/web/WebScopedUserGesture.h
+++ b/public/web/WebScopedUserGesture.h
@@ -34,11 +34,8 @@
 #include "../platform/WebPrivateOwnPtr.h"
 
 namespace blink {
-class UserGestureIndicator;
-}
-
-namespace blink {
 
+class UserGestureIndicator;
 class WebUserGestureToken;
 
 // An instance of this class, while kept alive, will indicate that we are in
@@ -65,7 +62,7 @@ private:
     BLINK_EXPORT void initializeWithToken(const WebUserGestureToken&);
     BLINK_EXPORT void reset();
 
-    WebPrivateOwnPtr<blink::UserGestureIndicator> m_indicator;
+    WebPrivateOwnPtr<UserGestureIndicator> m_indicator;
 };
 
 } // namespace blink