Fix crash on openning settings when DCHECK is on.

ash/shelf/app_list_shelf_item_delegate.cc

 // Copyright 2013 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 "ash/shelf/app_list_shelf_item_delegate.h"
 
 #include "ash/shelf/shelf_model.h"
 #include "ash/shell.h"
 #include "ash/strings/grit/ash_strings.h"
 #include "base/memory/ptr_util.h"
 #include "ui/app_list/app_list_switches.h"
 #include "ui/base/l10n/l10n_util.h"
 
 namespace ash {
 
-namespace {
-
-// An app id for the app list, used to identify the shelf item.
-static constexpr char kAppListId[] = "AppListId";
-
-}  // namespace
+// static
+const char AppListShelfItemDelegate::kAppListId[] =
+    "eiiblffaiacobmjejhcoookmokblahea";

[msw, 2017/05/05 21:45:04]

Instead of using an arc-specific formatting for the input via
ArcAppListPrefs::GetAppId("chrome.settings", "chrome.settings.ui"), could you
use crx_file::id_util::GenerateId("org.chromium.settings_ui") or similar for
this and the other new ids, and document what you used in comments with the
generated id literals?

[khmel, 2017/05/05 22:45:12]

That makes sense.

 
 // static
 void AppListShelfItemDelegate::CreateAppListItemAndDelegate(ShelfModel* model) {
   // Add the app list item to the shelf model.
   ShelfItem item;
   item.type = TYPE_APP_LIST;
   item.id = ShelfID(kAppListId);
   item.title = l10n_util::GetStringUTF16(IDS_ASH_SHELF_APP_LIST_LAUNCHER_TITLE);
   int index = model->Add(item);
   DCHECK_GE(index, 0);
@@ skipping 19 matching lines @@
 
 void AppListShelfItemDelegate::ExecuteCommand(uint32_t command_id,
                                               int32_t event_flags) {
   // This delegate does not support showing an application menu.
   NOTIMPLEMENTED();
 }
 
 void AppListShelfItemDelegate::Close() {}
 
 }  // namespace ash