Return node::Buffer as a printToPDF callback result.

atom/browser/api/atom_api_web_contents.h

@@ -52,7 +52,7 @@ class WebContents : public mate::EventEmitter,
                     public content::WebContentsObserver,
                     public content::GpuDataManagerObserver {
  public:
-  typedef base::Callback<void(int)> PrintToPDFCallback;
+  typedef base::Callback<void(v8::Local<v8::Value>)> PrintToPDFCallback;
 
   // Create from an existing WebContents.
   static mate::Handle<WebContents> CreateFrom(

atom/browser/api/lib/web-contents.coffee

@@ -89,7 +89,6 @@ wrapWebContents = (webContents) ->
       collate:true,
       shouldPrintBackgrounds:false,
       shouldPrintSelectionOnly:false
-      silent:false
 
     if options.landscape
       printingSetting.landscape = options.landscape