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

public/web/WebHistoryItem.h

Index: public/web/WebHistoryItem.h
diff --git a/public/web/WebHistoryItem.h b/public/web/WebHistoryItem.h
index 1257b4310c4bf53a9d5bbfa573b9432125b70ce7..8029cbb22560569ec9329675880ce05caed6e81f 100644
--- a/public/web/WebHistoryItem.h
+++ b/public/web/WebHistoryItem.h
@@ -35,9 +35,9 @@
 #include "../platform/WebPrivatePtr.h"
 #include "../platform/WebReferrerPolicy.h"
 
-namespace blink { class HistoryItem; }
-
 namespace blink {
+
+class HistoryItem;
 class WebHTTPBody;
 class WebString;
 class WebSerializedScriptValue;
@@ -116,13 +116,13 @@ public:
     BLINK_EXPORT WebVector<WebString> getReferencedFilePaths() const;
 
 #if BLINK_IMPLEMENTATION
-    WebHistoryItem(const WTF::PassRefPtr<blink::HistoryItem>&);
-    WebHistoryItem& operator=(const WTF::PassRefPtr<blink::HistoryItem>&);
-    operator WTF::PassRefPtr<blink::HistoryItem>() const;
+    WebHistoryItem(const WTF::PassRefPtr<HistoryItem>&);
+    WebHistoryItem& operator=(const WTF::PassRefPtr<HistoryItem>&);
+    operator WTF::PassRefPtr<HistoryItem>() const;
 #endif
 
 private:
-    WebPrivatePtr<blink::HistoryItem> m_private;
+    WebPrivatePtr<HistoryItem> m_private;
 };
 
 } // namespace blink