Added the 'internal' flag for guestview event info.

extensions/renderer/resources/guest_view/guest_view_events.js

Index: extensions/renderer/resources/guest_view/guest_view_events.js
diff --git a/extensions/renderer/resources/guest_view/guest_view_events.js b/extensions/renderer/resources/guest_view/guest_view_events.js
index caed8c88af8ad6fa8610980653b99e22c6d60545..f6a7e8308ed4a31af52b31061a73815a20702c23 100644
--- a/extensions/renderer/resources/guest_view/guest_view_events.js
+++ b/extensions/renderer/resources/guest_view/guest_view_events.js
@@ -41,6 +41,11 @@ function GuestViewEvents(view) {
 //     should be dispatched within this handler function (if desired). With no
 //     handler function, the DOM event will be dispatched by default each time
 //     the extension event is caught.
+// |internal| (default: false) specifies that the event will not be dispatched
+//     as a DOM event, and will also not appear as an on* property on the view’s
+//     element. A |handler| should be specified for all internal events, and
+//     |fields| and |cancelable| should be left unspecified (as they are only
+//     meaningful for DOM events).
 GuestViewEvents.EVENTS = {};
 
 // Sets up the handling of events.
@@ -57,7 +62,9 @@ GuestViewEvents.prototype.setupEvents = function() {
 
 // Sets up the handling of the |eventName| event.
 GuestViewEvents.prototype.setupEvent = function(eventName, eventInfo) {
-  this.setupEventProperty(eventName);
+  if (!eventInfo.internal) {
+    this.setupEventProperty(eventName);
+  }
 
   var listenerOpts = { instanceId: this.view.viewInstanceId };
   if (eventInfo.handler) {
@@ -67,6 +74,11 @@ GuestViewEvents.prototype.setupEvent = function(eventName, eventInfo) {
     return;
   }
 
+  // Internal events are not dispatched as DOM events.
+  if (eventInfo.internal) {
+    return;
+  }
+
   eventInfo.evt.addListener(function(e) {
     var domEvent = this.makeDomEvent(e, eventName);
     this.view.dispatchEvent(domEvent);
@@ -79,6 +91,11 @@ GuestViewEvents.prototype.makeDomEvent = function(event, eventName) {
   var eventInfo =
       GuestViewEvents.EVENTS[eventName] || this.getEvents()[eventName];
 
+  // Internal events are not dispatched as DOM events.
+  if (eventInfo.internal) {
+    return null;
+  }
+
   var details = { bubbles: true };
   if (eventInfo.cancelable) {
     details.cancelable = true;