Make showSaveDialog optionally async

src/application-delegate.coffee

@@ -153,10 +153,15 @@ class ApplicationDelegate
 
   showMessageDialog: (params) ->
 
-  showSaveDialog: (params) ->
-    if typeof params is 'string'
-      params = {defaultPath: params}
-    @getCurrentWindow().showSaveDialog(params)
+  showSaveDialog: (options, callback) ->
+    if callback?
+      # Async
+      @getCurrentWindow().showSaveDialog(options, callback)
+    else
+      # Sync
+      if typeof options is 'string'
+        options = {defaultPath: options}
+      @getCurrentWindow().showSaveDialog(options)
 
   playBeepSound: ->
     shell.beep()

src/atom-environment.js

@@ -1076,14 +1076,6 @@ class AtomEnvironment {
     return this.deserialize(state)
   }
 
-  showSaveDialog (callback) {
-    callback(this.showSaveDialogSync())
-  }
-
-  showSaveDialogSync (options = {}) {
-    this.applicationDelegate.showSaveDialog(options)
-  }
-
   async saveState (options, storageKey) {
     if (this.enablePersistence && this.project) {
       const state = this.serialize(options)

src/main-process/atom-window.coffee

@@ -294,12 +294,18 @@ class AtomWindow
       @browserWindow.reload() if result
     @loadedPromise
 
-  showSaveDialog: (params) ->
-    params = Object.assign({
+  showSaveDialog: (options, callback) ->
+    options = Object.assign({
       title: 'Save File',
       defaultPath: @representedDirectoryPaths[0]
-    }, params)
-    dialog.showSaveDialog(@browserWindow, params)
+    }, options)
+
+    if callback?
+      # Async
+      dialog.showSaveDialog(@browserWindow, options, callback)
+    else
+      # Sync
+      dialog.showSaveDialog(@browserWindow, options)
 
   toggleDevTools: -> @browserWindow.toggleDevTools()