cros: Add indication for inactive virtual desks.

When a user highlights an active desk in overview mode, ChromeVox
announces "Desk 1 (Active Desk) ...". However, when a user highlights
an inactive desk, ChromeVox announces "Desk 2 ...".

To make it more clear that the inactive desk is inactive, this CL adds
an indication that the desk is inactive. I.e. ChromeVox now announces
"Desk 2 (Inactive Desk) ...".

Test: manual
Bug: 1111988
Change-Id: I7e47ecd923fbfd2d7f8fe86531a03c87419cf23d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2364558Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Jeremy Chinsen <chinsenj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800660}

ash/ash_strings.grd

@@ -1096,6 +1096,9 @@ This file contains the strings for ash.
       <message name="IDS_ASH_DESKS_ACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP" desc="The accessibility tooltip read by screen readers for a highlighted active desk mini_view.">
         Active desk.
       </message>
+      <message name="IDS_ASH_DESKS_INACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP" desc="The accessibility tooltip read by screen readers for a highlighted inactive desk mini_view.">
+        Inactive desk.
+      </message>
 
       <!-- Status tray charging strings. -->
       <message name="IDS_ASH_STATUS_TRAY_LOW_POWER_CHARGER_TITLE" desc="The title of a notification indicating that a low-current USB charger has been connected.">

ash/ash_strings_grd/IDS_ASH_DESKS_INACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP.png.sha1

+c0011f1a7d59d0e49a62cc6be9fe822a6a1cd403
\ No newline at end of file

ash/wm/desks/desk_mini_view.cc

@@ -200,12 +200,12 @@ void DeskMiniView::GetAccessibleNodeData(ui::AXNodeData* node_data) {
     node_data->AddStringAttribute(ax::mojom::StringAttribute::kName,
                                   base::UTF16ToUTF8(desk_->name()));
 
-    if (desk_->is_active()) {
-      node_data->AddStringAttribute(
-          ax::mojom::StringAttribute::kValue,
-          l10n_util::GetStringUTF8(
-              IDS_ASH_DESKS_ACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP));
-    }
+    node_data->AddStringAttribute(
+        ax::mojom::StringAttribute::kValue,
+        l10n_util::GetStringUTF8(
+            desk_->is_active()
+                ? IDS_ASH_DESKS_ACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP
+                : IDS_ASH_DESKS_INACTIVE_DESK_MINIVIEW_A11Y_EXTRA_TIP));
   }
 
   if (DesksController::Get()->CanRemoveDesks()) {