Add support for exporting IPC messages from component DLLs.

ipc/ipc_message_utils_impl.h

Index: ipc/ipc_message_utils_impl.h
===================================================================
--- ipc/ipc_message_utils_impl.h	(revision 98434)
+++ ipc/ipc_message_utils_impl.h	(working copy)
@@ -12,14 +12,12 @@
 namespace IPC {
 
 template <class ParamType>
-MessageWithTuple<ParamType>::MessageWithTuple(
-    int32 routing_id, uint32 type, const RefParam& p)
-    : Message(routing_id, type, PRIORITY_NORMAL) {
-  WriteParam(this, p);
+void MessageSchema<ParamType>::Write(Message* msg, const RefParam& p) {
+  WriteParam(msg, p);
 }
 
 template <class ParamType>
-bool MessageWithTuple<ParamType>::Read(const Message* msg, Param* p) {
+bool MessageSchema<ParamType>::Read(const Message* msg, Param* p) {
   void* iter = NULL;
   if (ReadParam(msg, &iter, p))
     return true;
@@ -27,29 +25,22 @@
   return false;
 }
 
-// We can't migrate the template for Log() to MessageWithTuple, because each
-// subclass needs to have Log() to call Read(), which instantiates the above
-// template.
-
 template <class SendParamType, class ReplyParamType>
-MessageWithReply<SendParamType, ReplyParamType>::MessageWithReply(
-    int32 routing_id, uint32 type,
-    const RefSendParam& send,
-    const ReplyParam& reply)
-    : SyncMessage(routing_id, type, PRIORITY_NORMAL,
-                  new ParamDeserializer<ReplyParam>(reply)) {
-  WriteParam(this, send);
+void SyncMessageSchema<SendParamType, ReplyParamType>::Write(
+    Message* msg,
+    const RefSendParam& send) {
+  WriteParam(msg, send);
 }
 
 template <class SendParamType, class ReplyParamType>
-bool MessageWithReply<SendParamType, ReplyParamType>::ReadSendParam(
+bool SyncMessageSchema<SendParamType, ReplyParamType>::ReadSendParam(
     const Message* msg, SendParam* p) {
   void* iter = SyncMessage::GetDataIterator(msg);
   return ReadParam(msg, &iter, p);
 }
 
 template <class SendParamType, class ReplyParamType>
-bool MessageWithReply<SendParamType, ReplyParamType>::ReadReplyParam(
+bool SyncMessageSchema<SendParamType, ReplyParamType>::ReadReplyParam(
     const Message* msg, typename TupleTypes<ReplyParam>::ValueTuple* p) {
   void* iter = SyncMessage::GetDataIterator(msg);
   return ReadParam(msg, &iter, p);