Use explicit WebString conversions in remaining content files

content/renderer/renderer_webcookiejar_impl.cc

 // Copyright (c) 2010 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 "content/renderer/renderer_webcookiejar_impl.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "content/common/frame_messages.h"
 #include "content/public/renderer/content_renderer_client.h"
 #include "content/renderer/render_frame_impl.h"
 #include "content/renderer/render_thread_impl.h"
 
 using blink::WebString;
 using blink::WebURL;
 
 namespace content {
 
 void RendererWebCookieJarImpl::setCookie(
     const WebURL& url, const WebURL& first_party_for_cookies,
     const WebString& value) {
-  std::string value_utf8 = base::UTF16ToUTF8(base::StringPiece16(value));
+  std::string value_utf8 = value.utf8(
+      WebString::UTF8ConversionMode::kStrictReplacingErrorsWithFFFD);
   RenderThreadImpl::current()->render_frame_message_filter()->SetCookie(
       sender_->GetRoutingID(), url, first_party_for_cookies, value_utf8);
 }
 
 WebString RendererWebCookieJarImpl::cookies(
     const WebURL& url, const WebURL& first_party_for_cookies) {
   std::string value_utf8;
   RenderThreadImpl::current()->render_frame_message_filter()->GetCookies(
       sender_->GetRoutingID(), url, first_party_for_cookies, &value_utf8);
   return WebString::fromUTF8(value_utf8);
 }
 
 bool RendererWebCookieJarImpl::cookiesEnabled(
     const WebURL& url, const WebURL& first_party_for_cookies) {
   bool cookies_enabled = false;
   sender_->Send(new FrameHostMsg_CookiesEnabled(
       sender_->GetRoutingID(), url, first_party_for_cookies, &cookies_enabled));
   return cookies_enabled;
 }
 
 }  // namespace content