Add zoomFactor to guest params

lib/browser/guest-view-manager.js

@@ -179,6 +179,7 @@ var attachGuest = function (embedder, elementInstanceId, guestInstanceId, params
     guestInstanceId: guestInstanceId,
     nodeIntegration: (ref1 = params.nodeintegration) != null ? ref1 : false,
     plugins: params.plugins,
+    zoomFactor: params.zoomFactor,
     webSecurity: !params.disablewebsecurity,
     blinkFeatures: params.blinkfeatures
   }

lib/renderer/web-view/web-view.js

@@ -223,7 +223,8 @@ var WebViewImpl = (function () {
     var attribute, attributeName, css, elementRect, params, ref1
     params = {
       instanceId: this.viewInstanceId,
-      userAgentOverride: this.userAgentOverride
+      userAgentOverride: this.userAgentOverride,
+      zoomFactor: webFrame.getZoomFactor()
     }
     ref1 = this.attributes
     for (attributeName in ref1) {