Revert 178037

content/public/common/common_param_traits.h

Index: content/public/common/common_param_traits.h
===================================================================
--- content/public/common/common_param_traits.h	(revision 178042)
+++ content/public/common/common_param_traits.h	(working copy)
@@ -182,25 +182,8 @@
     l->append(")");
   }
 };
+#endif
 
-#if defined(USE_AURA)
-template <>
-struct ParamTraits<HWND> {
-  typedef HWND param_type;
-  static void Write(Message* m, const param_type& p) {
-    m->WriteUInt32(reinterpret_cast<uint32>(p));
-  }
-  static bool Read(const Message* m, PickleIterator* iter, param_type* r) {
-    DCHECK_EQ(sizeof(param_type), sizeof(uint32));
-    return m->ReadUInt32(iter, reinterpret_cast<uint32*>(r));
-  }
-  static void Log(const param_type& p, std::string* l) {
-    l->append("<HWND>");
-  }
-};
-#endif  // defined(USE_AURA)
-#endif  // defined(OS_WIN)
-
 #if defined(USE_X11)
 template<>
 struct ParamTraits<TransportDIB::Id> {