[Extensions Bindings] Request JS execution from messaging bindings

extensions/renderer/js_extension_bindings_system.cc

 // 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.
 
 #include "extensions/renderer/js_extension_bindings_system.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_split.h"
 #include "content/public/child/v8_value_converter.h"
 #include "content/public/common/content_switches.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_api.h"
 #include "extensions/common/extension_urls.h"
 #include "extensions/common/extensions_client.h"
 #include "extensions/common/features/feature.h"
 #include "extensions/common/features/feature_provider.h"
 #include "extensions/common/manifest_constants.h"
 #include "extensions/common/manifest_handlers/externally_connectable.h"
 #include "extensions/renderer/binding_generating_native_handler.h"
+#include "extensions/renderer/event_bindings.h"
 #include "extensions/renderer/renderer_extension_registry.h"
 #include "extensions/renderer/resource_bundle_source_map.h"
 #include "extensions/renderer/script_context.h"
 #include "gin/converter.h"
 #include "v8/include/v8.h"
 
 namespace extensions {
 
 namespace {
 
@@ skipping 235 matching lines @@
       arguments.push_back(
           converter->ToV8Value(filtering_info, context->v8_context()));
     }
   }
 
   context->module_system()->CallModuleMethodSafe(
       kEventBindings, kEventDispatchFunction, arguments.size(),
       arguments.data());
 }
 
+bool JsExtensionBindingsSystem::HasEventListenerInContext(
+    const std::string& event_name,
+    ScriptContext* context) {
+  return EventBindings::HasListener(context, event_name);
+}
+
 void JsExtensionBindingsSystem::RegisterBinding(
     const std::string& api_name,
     const std::string& api_bind_name,
     ScriptContext* context) {
   std::string bind_name;
   v8::Local<v8::Object> bind_object =
       GetOrCreateBindObjectIfAvailable(api_bind_name, &bind_name, context);
 
   // Empty if the bind object failed to be created, probably because the
   // extension overrode chrome with a non-object, e.g. window.chrome = true.
@@ skipping 25 matching lines @@
         std::unique_ptr<NativeHandler>(
             new BindingGeneratingNativeHandler(context, api_name, "binding")));
     module_system->SetNativeLazyField(bind_object, bind_name, api_bind_name,
                                       "binding");
   } else {
     module_system->SetLazyField(bind_object, bind_name, api_name, "binding");
   }
 }
 
 }  // namespace extensions