[Extensions Bindings] Return result from event dispatch

extensions/renderer/api_event_handler.cc

Index: extensions/renderer/api_event_handler.cc
diff --git a/extensions/renderer/api_event_handler.cc b/extensions/renderer/api_event_handler.cc
index 7c37c60d6cd0a93a64d48f84f3a0f1ef7ed883e4..212afeeef04bfce23d733b3bce78cabbe50e587a 100644
--- a/extensions/renderer/api_event_handler.cc
+++ b/extensions/renderer/api_event_handler.cc
@@ -108,8 +108,11 @@ void DispatchEvent(const v8::FunctionCallbackInfo<v8::Value>& info) {
 
 APIEventHandler::APIEventHandler(
     const binding::RunJSFunction& call_js,
+    const binding::RunJSFunctionSync& call_js_sync,
     const EventListenersChangedMethod& listeners_changed)
-    : call_js_(call_js), listeners_changed_(listeners_changed) {}
+    : call_js_(call_js),
+      call_js_sync_(call_js_sync),
+      listeners_changed_(listeners_changed) {}
 APIEventHandler::~APIEventHandler() {}
 
 v8::Local<v8::Object> APIEventHandler::CreateEventInstance(
@@ -139,9 +142,10 @@ v8::Local<v8::Object> APIEventHandler::CreateEventInstance(
         base::MakeUnique<UnfilteredEventListeners>(updated, max_listeners);
   }
 
-  gin::Handle<EventEmitter> emitter_handle = gin::CreateHandle(
-      context->GetIsolate(),
-      new EventEmitter(supports_filters, std::move(listeners), call_js_));
+  gin::Handle<EventEmitter> emitter_handle =
+      gin::CreateHandle(context->GetIsolate(),
+                        new EventEmitter(supports_filters, std::move(listeners),
+                                         call_js_, call_js_sync_));
   CHECK(!emitter_handle.IsEmpty());
   v8::Local<v8::Value> emitter_value = emitter_handle.ToV8();
   CHECK(emitter_value->IsObject());
@@ -161,9 +165,10 @@ v8::Local<v8::Object> APIEventHandler::CreateAnonymousEventInstance(
   std::unique_ptr<APIEventListeners> listeners =
       base::MakeUnique<UnfilteredEventListeners>(
           base::Bind(&DoNothingOnListenersChanged), binding::kNoListenerMax);
-  gin::Handle<EventEmitter> emitter_handle = gin::CreateHandle(
-      context->GetIsolate(),
-      new EventEmitter(supports_filters, std::move(listeners), call_js_));
+  gin::Handle<EventEmitter> emitter_handle =
+      gin::CreateHandle(context->GetIsolate(),
+                        new EventEmitter(supports_filters, std::move(listeners),
+                                         call_js_, call_js_sync_));
   CHECK(!emitter_handle.IsEmpty());
   v8::Local<v8::Object> emitter_object = emitter_handle.ToV8().As<v8::Object>();
   data->anonymous_emitters.push_back(