cocoa: add --use-views-task-manager

chrome/browser/ui/cocoa/task_manager_mac.mm

 // Copyright (c) 2012 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/ui/cocoa/task_manager_mac.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <vector>
 
+#include "base/command_line.h"
 #include "base/mac/bundle_locations.h"
 #include "base/macros.h"
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/task_manager/task_manager_interface.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_dialogs.h"
 #import "chrome/browser/ui/cocoa/window_size_autosaver.h"
 #include "chrome/browser/ui/task_manager/task_manager_columns.h"
+#include "chrome/common/chrome_switches.h"

[tapted, 2017/03/02 22:44:39]

I think base/feature_list.h is the shiny new way to do all this. Pretty sure
then the changes are wholly contained in task_manager_mac.mm, plus we get
easy/automatic Finch integration if we want that, and a nicer avenue to add a
chrome://flag (if we want that).

The downside is just a little less convenience on the command line (i.e.
--enable_features=..).

Actually, I think we want the chrome://flag entry too -- wdyt?

[shrike, 2017/03/02 23:58:05]

We do need a chrome://flag entry. I look at MacViews/Harmony changes in Canary
and don't generally run it from the command line.

[tapted, 2017/03/07 22:52:26]

Per ^^^, is there a reason to not want to use base::FeatureList?

 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_source.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_skia_util_mac.h"
 
 namespace {
 
 NSString* ColumnIdentifier(int id) {
   return [NSString stringWithFormat:@"%d", id];
 }
 
+bool ShouldUseViewsTaskManager() {
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kUseViewsTaskManager);
+}
+
 }  // namespace
 
 @interface TaskManagerWindowController (Private)
 - (NSTableColumn*)addColumnWithData:
     (const task_manager::TableColumnData&)columnData;
 - (void)setUpTableColumns;
 - (void)setUpTableHeaderContextMenu;
 - (void)toggleColumn:(id)sender;
 - (void)adjustSelectionAndEndProcessButton;
 - (void)deselectRows;
@@ skipping 584 matching lines @@
   if (instance_)
     [instance_->window_controller_ close];
 }
 
 }  // namespace task_manager
 
 namespace chrome {
 
 // Declared in browser_dialogs.h.
 task_manager::TaskManagerTableModel* ShowTaskManager(Browser* browser) {
+  if (ShouldUseViewsTaskManager())
+    return chrome::ShowTaskManagerViews(browser);
   return task_manager::TaskManagerMac::Show();
 }
 
 void HideTaskManager() {
+  if (ShouldUseViewsTaskManager())
+    return chrome::HideTaskManagerViews();
   task_manager::TaskManagerMac::Hide();
 }
 
 }  // namespace chrome