Move the Mac Task Manager to the new backend code.

chrome/browser/task_manager/web_contents_information.cc

Index: chrome/browser/task_manager/web_contents_information.cc
diff --git a/chrome/browser/task_manager/web_contents_information.cc b/chrome/browser/task_manager/web_contents_information.cc
deleted file mode 100644
index f2f7b513668c5b22f1a1c655dd6fc6ee4b199561..0000000000000000000000000000000000000000
--- a/chrome/browser/task_manager/web_contents_information.cc
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2014 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_manager/web_contents_information.h"
-#include "content/public/browser/notification_service.h"
-#include "content/public/browser/notification_types.h"
-
-namespace task_manager {
-
-WebContentsInformation::WebContentsInformation() {}
-
-WebContentsInformation::~WebContentsInformation() {}
-
-NotificationObservingWebContentsInformation::
-    NotificationObservingWebContentsInformation() {}
-
-NotificationObservingWebContentsInformation::
-    ~NotificationObservingWebContentsInformation() {}
-
-void NotificationObservingWebContentsInformation::StartObservingCreation(
-    const NewWebContentsCallback& callback) {
-  observer_callback_ = callback;
-  registrar_.Add(this,
-                 content::NOTIFICATION_WEB_CONTENTS_CONNECTED,

[ncarter (slow), 2016/08/02 19:49:36]

Nice.

This puts us down to only one usage of this infernal notification.

[Avi (use Gerrit), 2016/08/02 20:06:56]

Acknowledged.

-                 content::NotificationService::AllBrowserContextsAndSources());
-}
-
-void NotificationObservingWebContentsInformation::StopObservingCreation() {
-  registrar_.Remove(
-      this,
-      content::NOTIFICATION_WEB_CONTENTS_CONNECTED,
-      content::NotificationService::AllBrowserContextsAndSources());
-  observer_callback_.Reset();
-}
-
-void NotificationObservingWebContentsInformation::Observe(
-    int type,
-    const content::NotificationSource& source,
-    const content::NotificationDetails& details) {
-  DCHECK_EQ(content::NOTIFICATION_WEB_CONTENTS_CONNECTED, type);
-
-  content::WebContents* web_contents =
-      content::Source<content::WebContents>(source).ptr();
-  if (CheckOwnership(web_contents))
-    observer_callback_.Run(web_contents);
-}
-
-}  // namespace task_manager