Fix bugs in the new task manager Impl so that ported old browsertests pass

chrome/browser/task_management/providers/web_contents/devtools_task.cc

 // Copyright 2015 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 "chrome/browser/task_management/providers/web_contents/devtools_task.h"
 
 #include "content/public/browser/web_contents.h"
 
 namespace task_management {
 
 DevToolsTask::DevToolsTask(content::WebContents* web_contents)
-    : RendererTask(RendererTask::GetTitleFromWebContents(web_contents),
-                   RendererTask::GetFaviconFromWebContents(web_contents),
-                   web_contents,
-                   web_contents->GetRenderProcessHost()) {
+    : TabContentsTask(web_contents) {
 }
 
 DevToolsTask::~DevToolsTask() {
 }
 
-void DevToolsTask::UpdateTitle() {
-  // In the case of a devtools tab, we just ignore this event.
-}
-
-void DevToolsTask::UpdateFavicon() {
-  // In the case of a devtools tab, we just ignore this event.
-}
-
 }  // namespace task_management