Make it safe to use sendSync

atom/renderer/api/lib/ipc-renderer.coffee

@@ -1,9 +1,17 @@
+{EventEmitter} = require 'events'
+
 binding = process.atomBinding 'ipc'
 v8Util  = process.atomBinding 'v8_util'
 
 # Created by init.coffee.
 ipcRenderer = v8Util.getHiddenValue global, 'ipc'
 
+# Delay the callback to next tick in case the browser is still in the middle
+# of sending a message while the callback sends a sync message to browser,
+# which can fail sometimes.
+ipcRenderer.emit = (args...) ->
+  setTimeout (-> EventEmitter::emit.call ipcRenderer, args...), 0
+
 ipcRenderer.send = (args...) ->
   binding.send 'ipc-message', [args...]