No more plan for ipc.sendSync in browser.

I want the browser to be fully asynchronous, so sending synchronous
messages from browser to renderer will be unacceptable.

common/api/api_messages.h

@@ -27,8 +27,3 @@ IPC_SYNC_MESSAGE_ROUTED2_1(AtomViewHostMsg_Message_Sync,
 IPC_MESSAGE_ROUTED2(AtomViewMsg_Message,
                     std::string /* channel */,
                     ListValue /* arguments */)
-
-IPC_SYNC_MESSAGE_ROUTED2_1(AtomViewMsg_Message_Sync,
-                           std::string /* channel */,
-                           ListValue /* arguments */,
-                           DictionaryValue /* result */)

renderer/api/lib/ipc.coffee

@@ -5,11 +5,9 @@ class Ipc extends EventEmitter
   constructor: ->
     process.on 'ATOM_INTERNAL_MESSAGE', (args...) =>
       @emit(args...)
-    process.on 'ATOM_INTERNAL_MESSAGE_SYNC', (args...) =>
-      @emit(args...)
 
   send: (args...) ->
-    @sendChannel('message', args...)
+    ipc.send('ATOM_INTERNAL_MESSAGE', 'message', args...)
 
   sendChannel: (args...) ->
     ipc.send('ATOM_INTERNAL_MESSAGE', args...)