Move the Mac Task Manager to the new backend code.

chrome/browser/task_management/task_manager_tester.h

 // 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.
 
 #ifndef CHROME_BROWSER_TASK_MANAGEMENT_TASK_MANAGER_TESTER_H_
 #define CHROME_BROWSER_TASK_MANAGEMENT_TASK_MANAGER_TESTER_H_
 
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/strings/string16.h"
 #include "chrome/browser/task_management/task_manager_browsertest_util.h"
 
 namespace task_management {
 
-// An adapter that abstracts away the difference of old vs. new task manager.
+// An adapter to simplify testing the task manager.
 class TaskManagerTester {

[afakhry, 2016/08/02 16:41:33]

Maybe this adapter isn't needed anymore, but that's certainly for a later CL.

[Avi (use Gerrit), 2016/08/02 17:39:44]

Acknowledged.

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

I think it's fine to leave this mostly intact. We need some friend code to do
the model-getting and to interpose on the table model observer, and we need
GetColumnValue so that WaitForTaskManagerStatToExceed works properly. So we need
some test code here.

The main thing we could do would be to make this class nonvirtual, and merge
TaskManagerTester and TaskManagerTesterImpl. I'd approve that CL, but I'm not
sure it actually improves the code other than reducing the line count slightly.

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

For followup, if nothing else. This CL is big enough.

  public:
   using ColumnSpecifier = browsertest_util::ColumnSpecifier;
 
   // Creates a TaskManagerTester backed by the current task manager. The task
   // manager should already be visible when you call this function. |callback|,
   // if not a null callback, will be invoked when the underlying model changes.
   static std::unique_ptr<TaskManagerTester> Create(
       const base::Closure& callback);
 
-  // If using a legacy task manager, refresh the model.
-  static void MaybeRefreshLegacyInstance();
-
   virtual ~TaskManagerTester() {}
 
   // Get the number of rows currently in the task manager.
   virtual int GetRowCount() = 0;
 
   // Get the title text of a particular |row|.
   virtual base::string16 GetRowTitle(int row) = 0;
 
   // Hide or show a column. If a column is not visible its stats are not
   // necessarily gathered.
   virtual void ToggleColumnVisibility(ColumnSpecifier column) = 0;
 
   // Get the value of a column as an int64. Memory values are in bytes.
   virtual int64_t GetColumnValue(ColumnSpecifier column, int row) = 0;
 
   // If |row| is associated with a WebContents, return its SessionID. Otherwise,
   // return -1.
   virtual int32_t GetTabId(int row) = 0;
 
   // Kill the process of |row|.
   virtual void Kill(int row) = 0;
 
   // Gets the start index and length of the group to which the task at
   // |row_index| belongs.
   virtual void GetRowsGroupRange(int row, int* out_start, int* out_length) = 0;
-
- private:
-  // Always creates a tester for the non-legacy TaskManager.
-  static std::unique_ptr<TaskManagerTester> CreateDefault(
-      const base::Closure& callback);
 };
 
 }  // namespace task_management
 
 #endif  // CHROME_BROWSER_TASK_MANAGEMENT_TASK_MANAGER_TESTER_H_