Revert 178043

content/public/common/common_param_traits.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file is used to define IPC::ParamTraits<> specializations for a number
 // of types so that they can be serialized over IPC.  IPC::ParamTraits<>
 // specializations for basic types (like int and std::string) and types in the
 // 'base' project can be found in ipc/ipc_message_utils.h.  This file contains
 // specializations for types that are used by the content code, and which need
 // manual serialization code.  This is usually because they're not structs with
@@ skipping 164 matching lines @@
             ReadParam(m, iter, &r->sequence_num));
   }
   static void Log(const param_type& p, std::string* l) {
     l->append("TransportDIB(");
     LogParam(p.handle, l);
     l->append(", ");
     LogParam(p.sequence_num, l);
     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> {
   typedef TransportDIB::Id param_type;
   static void Write(Message* m, const param_type& p) {
     WriteParam(m, p.shmkey);
   }
   static bool Read(const Message* m, PickleIterator* iter, param_type* r) {
     return ReadParam(m, iter, &r->shmkey);
@@ skipping 14 matching lines @@
   // Note: This function expects parameter |r| to be of type &SkBitmap since
   // r->SetConfig() and r->SetPixels() are called.
   static bool Read(const Message* m, PickleIterator* iter, param_type* r);
 
   static void Log(const param_type& p, std::string* l);
 };
 
 }  // namespace IPC
 
 #endif  // CONTENT_PUBLIC_COMMON_COMMON_PARAM_TRAITS_H_