Adding slightly clearer separation between SW and EmbeddedWorker (still incomplete)

content/common/service_worker/embedded_worker_messages.h

Index: content/common/service_worker/embedded_worker_messages.h
diff --git a/content/common/service_worker/embedded_worker_messages.h b/content/common/service_worker/embedded_worker_messages.h
index 9f904ee3b7eb93cfd262d516788c1cfb862f96f0..d38e91f2e25c72c6b9e22afb23183a4caf1840ff 100644
--- a/content/common/service_worker/embedded_worker_messages.h
+++ b/content/common/service_worker/embedded_worker_messages.h
@@ -6,7 +6,7 @@
 
 #include <string>
 
-#include "content/common/service_worker/service_worker_types.h"
+#include "ipc/ipc_message.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/ipc_param_traits.h"
 #include "url/gurl.h"
@@ -14,12 +14,6 @@
 #undef IPC_MESSAGE_EXPORT
 #define IPC_MESSAGE_EXPORT CONTENT_EXPORT
 
-IPC_STRUCT_TRAITS_BEGIN(content::ServiceWorkerFetchRequest)
-  IPC_STRUCT_TRAITS_MEMBER(url)
-  IPC_STRUCT_TRAITS_MEMBER(method)
-  IPC_STRUCT_TRAITS_MEMBER(headers)
-IPC_STRUCT_TRAITS_END()
-
 #define IPC_MESSAGE_START EmbeddedWorkerMsgStart
 
 // Browser -> Renderer message to create a new embedded worker context.
@@ -41,6 +35,11 @@ IPC_MESSAGE_CONTROL2(EmbeddedWorkerHostMsg_WorkerStarted,
 IPC_MESSAGE_CONTROL1(EmbeddedWorkerHostMsg_WorkerStopped,
                      int /* embedded_worker_id */)
 
+// Renderer ->Browser message to send message.
+IPC_MESSAGE_CONTROL2(EmbeddedWorkerHostMsg_SendMessageToBrowser,
+                     int /* embedded_worker_id */,
+                     IPC::Message /* message */)
+
 // ---------------------------------------------------------------------------
 // For EmbeddedWorkerContext related messages, which are directly sent from
 // browser to the worker thread in the child process. We use a new message class
@@ -49,7 +48,8 @@ IPC_MESSAGE_CONTROL1(EmbeddedWorkerHostMsg_WorkerStopped,
 #undef IPC_MESSAGE_START
 #define IPC_MESSAGE_START EmbeddedWorkerContextMsgStart
 
-IPC_MESSAGE_CONTROL3(EmbeddedWorkerContextMsg_FetchEvent,
+// Browser -> Renderer message to send message.
+IPC_MESSAGE_CONTROL3(EmbeddedWorkerContextMsg_SendMessageToWorker,
                      int /* thread_id */,
                      int /* embedded_worker_id */,
-                     content::ServiceWorkerFetchRequest)
+                     IPC::Message /* message */)