[Extensions Bindings] Request JS execution from messaging bindings

extensions/renderer/js_extension_bindings_system.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_JS_EXTENSION_BINDINGS_SYSTEM_H_
 #define EXTENSIONS_RENDERER_JS_EXTENSION_BINDINGS_SYSTEM_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 12 matching lines @@
   ~JsExtensionBindingsSystem() override;
 
   // ExtensionBindingsSystem:
   void DidCreateScriptContext(ScriptContext* context) override;
   void WillReleaseScriptContext(ScriptContext* context) override;
   void UpdateBindingsForContext(ScriptContext* context) override;
   void DispatchEventInContext(const std::string& event_name,
                               const base::ListValue* event_args,
                               const base::DictionaryValue* filtering_info,
                               ScriptContext* context) override;
+  bool HasEventListenerInContext(const std::string& event_name,
+                                 ScriptContext* context) override;
   void HandleResponse(int request_id,
                       bool success,
                       const base::ListValue& response,
                       const std::string& error) override;
   RequestSender* GetRequestSender() override;
 
  private:
   void RegisterBinding(const std::string& api_name,
                        const std::string& api_bind_name,
                        ScriptContext* context);
 
   ResourceBundleSourceMap* source_map_ = nullptr;
 
   std::unique_ptr<RequestSender> request_sender_;
 
   DISALLOW_COPY_AND_ASSIGN(JsExtensionBindingsSystem);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_JS_EXTENSION_BINDINGS_SYSTEM_H_