[Extensions Bindings] Remove ScriptContext::DispatchEvent

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"
@@ skipping 243 matching lines @@
   v8::Context::Scope context_scope(context->v8_context());
 
   std::vector<v8::Local<v8::Value>> arguments;
   arguments.push_back(gin::StringToSymbol(context->isolate(), event_name));
 
   {
     std::unique_ptr<content::V8ValueConverter> converter(
         content::V8ValueConverter::create());
     arguments.push_back(
         converter->ToV8Value(event_args, context->v8_context()));
-    if (!filtering_info->empty()) {
+    if (filtering_info && !filtering_info->empty()) {
       arguments.push_back(
           converter->ToV8Value(filtering_info, context->v8_context()));
     }
   }
 
   context->module_system()->CallModuleMethodSafe(
       kEventBindings, kEventDispatchFunction, arguments.size(),
       arguments.data());
 }
 
@@ skipping 35 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