[Content] Update V8ValueConverter::create to return a std::unique_ptr

extensions/renderer/web_request_hooks.cc

 // Copyright 2017 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/web_request_hooks.h"
 
 #include "base/values.h"
 #include "content/public/child/v8_value_converter.h"
 #include "extensions/common/extension_api.h"
 #include "extensions/renderer/api_binding_hooks.h"
@@ skipping 41 matching lines @@
   }
 
   // The JS validates that the extra parameters passed to the web request event
   // match the expected schema. We need to initialize the event with that
   // schema.
   const base::DictionaryValue* event_spec =
       ExtensionAPI::GetSharedInstance()->GetSchema(event_name);
   DCHECK(event_spec);
   const base::ListValue* extra_params = nullptr;
   CHECK(event_spec->GetList("extraParameters", &extra_params));
-  std::unique_ptr<content::V8ValueConverter> converter(
-      content::V8ValueConverter::create());
   v8::Local<v8::Value> extra_parameters_spec =
-      converter->ToV8Value(extra_params, context);
+      content::V8ValueConverter::Create()->ToV8Value(extra_params, context);
 
   v8::Local<v8::Function> get_event = get_event_value.As<v8::Function>();
   v8::Local<v8::Value> args[] = {
       gin::StringToSymbol(isolate, event_name),
       v8::Undefined(isolate),  // opt_argSchemas are ignored.
       extra_parameters_spec,
       // opt_eventOptions and opt_webViewInstanceId are ignored.
   };
   *event_out =
       run_js_sync.Run(get_event, context, arraysize(args), args).Get(isolate);
   return true;
 }
 
 }  // namespace extensions