[Extensions Bindings] Return result from event dispatch

extensions/renderer/api_event_handler.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef EXTENSIONS_RENDERER_API_EVENT_HANDLER_H_
 #define EXTENSIONS_RENDERER_API_EVENT_HANDLER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 21 matching lines @@
   // removeListener, rather than through something like context destruction.
   // See also APIEventListeners.
   using EventListenersChangedMethod =
       base::Callback<void(const std::string& event_name,
                           binding::EventListenersChanged,
                           const base::DictionaryValue* filter,
                           bool was_manual,
                           v8::Local<v8::Context>)>;
 
   APIEventHandler(const binding::RunJSFunction& call_js,
+                  const binding::RunJSFunctionSync& call_js_sync,
                   const EventListenersChangedMethod& listeners_changed);
   ~APIEventHandler();
 
   // Returns a new v8::Object for an event with the given |event_name|. If
   // |notify_on_change| is true, notifies whenever listeners state is changed.
   v8::Local<v8::Object> CreateEventInstance(const std::string& event_name,
                                             bool supports_filters,
                                             int max_listeners,
                                             bool notify_on_change,
                                             v8::Local<v8::Context> context);
@@ skipping 31 matching lines @@
 
   // Invalidates listeners for the given |context|. It's a shame we have to
   // have this separately (as opposed to hooking into e.g. a PerContextData
   // destructor), but we need to do this before the context is fully removed
   // (because the associated extension ScriptContext needs to be valid).
   void InvalidateContext(v8::Local<v8::Context> context);
 
  private:
   // Method to run a given v8::Function. Curried in for testing.
   binding::RunJSFunction call_js_;
+  binding::RunJSFunctionSync call_js_sync_;
 
   EventListenersChangedMethod listeners_changed_;
 
   // The associated EventFilter; shared across all contexts and events.
   EventFilter event_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(APIEventHandler);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_API_EVENT_HANDLER_H_