Cleanup namespace usage in public/platform/{Web[P-W]*,linux/*}.h

public/platform/WebSize.h

Index: public/platform/WebSize.h
diff --git a/public/platform/WebSize.h b/public/platform/WebSize.h
index f137ac381bd0e7962de1eb8522ba359889551e47..fb1d8920bf97d24421763043b6b027e04cd65f5a 100644
--- a/public/platform/WebSize.h
+++ b/public/platform/WebSize.h
@@ -63,22 +63,22 @@ struct WebSize {
     }
 
 #if INSIDE_BLINK
-    WebSize(const blink::IntSize& s)
+    WebSize(const IntSize& s)
         : width(s.width())
         , height(s.height())
     {
     }
 
-    WebSize& operator=(const blink::IntSize& s)
+    WebSize& operator=(const IntSize& s)
     {
         width = s.width();
         height = s.height();
         return *this;
     }
 
-    operator blink::IntSize() const
+    operator IntSize() const
     {
-        return blink::IntSize(width, height);
+        return IntSize(width, height);
     }
 #else
     WebSize(const gfx::Size& s)