cros: Make the Autohide Shelf context menu option toggle

The Autohide Shelf context menu option lets the user make
the shelf hide when a window is maximized. This option used to
have a check mark signifying that autohide was enabled. With touchable
app context menus, there is no check mark.

To work like a checkmark, we will add a new selection option which
toggles with "Autohide Shelf". It is called "Always Show Shelf".

Bug: 875781
Change-Id: I6ed9f42cd6ac3e67f70110ea69944cc18a7abba7
Reviewed-on: https://chromium-review.googlesource.com/1188888Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Alex Newcomer <newcomer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586027}

ash/ash_strings.grd

@@ -145,6 +145,9 @@ This file contains the strings for ash.
       <message name="IDS_ASH_SHELF_CONTEXT_MENU_AUTO_HIDE" desc="Title of the menu item in the context menu for auto-hiding the shelf when the current window is not maximized">
         Autohide shelf
       </message>
+      <message name="IDS_ASH_SHELF_CONTEXT_MENU_ALWAYS_SHOW_SHELF" desc="Title of the menu item in the context menu for always showing the shelf">
+        Always Show Shelf
+      </message>
       <message name="IDS_ASH_SHELF_CONTEXT_MENU_POSITION" desc="Title of the menu item in the context menu for aligning the shelf">
         Shelf position
       </message>

ash/resources/vector_icons/BUILD.gn

@@ -9,6 +9,7 @@ aggregate_vector_icons("ash_vector_icons") {
   icon_directory = "."
 
   icons = [
+    "always_show_shelf.icon",
     "auto_hide.icon",
     "captive_portal.icon",
     "check_circle.icon",

ash/resources/vector_icons/always_show_shelf.icon

+// Copyright 2018 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.
+
+CANVAS_DIMENSIONS, 20,
+MOVE_TO, 4, 11,
+R_H_LINE_TO, 12,
+R_V_LINE_TO, 2,
+H_LINE_TO, 4,
+V_LINE_TO, 11,
+CLOSE,
+R_MOVE_TO, 0, -8,
+R_H_LINE_TO, 12,
+R_ARC_TO, 2, 2, 0, 0, 1, 2, 2,
+R_V_LINE_TO, 10,
+R_ARC_TO, 2, 2, 0, 0, 1, -2, 2,
+H_LINE_TO, 4,
+R_ARC_TO, 2, 2, 0, 0, 1, -2, -2,
+V_LINE_TO, 5,
+R_ARC_TO, 2, 2, 0, 0, 1, 2, -2,
+CLOSE,
+R_MOVE_TO, 0, 2,
+R_V_LINE_TO, 10,
+R_H_LINE_TO, 12,
+V_LINE_TO, 5,
+H_LINE_TO, 4,
+CLOSE

ash/shelf/shelf_context_menu_model.cc

@@ -76,18 +76,23 @@ void AddLocalMenuItems(MenuItemList* menu, int64_t display_id) {
   if (CanUserModifyShelfAutoHide(prefs) && !IsFullScreenMode(display_id) &&
       !skip_clamshell_only_options) {
     mojom::MenuItemPtr auto_hide(mojom::MenuItem::New());
+    const bool is_autohide_set =
+        GetShelfAutoHideBehaviorPref(prefs, display_id) ==
+        SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
     if (features::IsTouchableAppContextMenuEnabled()) {
       auto_hide->type = ui::MenuModel::TYPE_COMMAND;
-      auto_hide->image =
-          gfx::CreateVectorIcon(kAutoHideIcon, menu_config.touchable_icon_size,
-                                menu_config.touchable_icon_color);
+      auto_hide->image = gfx::CreateVectorIcon(
+          is_autohide_set ? kAlwaysShowShelfIcon : kAutoHideIcon,
+          menu_config.touchable_icon_size, menu_config.touchable_icon_color);
+      auto_hide->label = GetStringUTF16(
+          is_autohide_set ? IDS_ASH_SHELF_CONTEXT_MENU_ALWAYS_SHOW_SHELF
+                          : IDS_ASH_SHELF_CONTEXT_MENU_AUTO_HIDE);
     } else {
+      auto_hide->label = GetStringUTF16(IDS_ASH_SHELF_CONTEXT_MENU_AUTO_HIDE);
       auto_hide->type = ui::MenuModel::TYPE_CHECK;
-      auto_hide->checked = GetShelfAutoHideBehaviorPref(prefs, display_id) ==
-                           SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
+      auto_hide->checked = is_autohide_set;
     }
     auto_hide->command_id = ShelfContextMenuModel::MENU_AUTO_HIDE;
-    auto_hide->label = GetStringUTF16(IDS_ASH_SHELF_CONTEXT_MENU_AUTO_HIDE);
     auto_hide->enabled = !is_tablet_mode;
     menu->push_back(std::move(auto_hide));
   }