Add an accessible name to the restart button

ash/system/tray/tray_views.cc

Index: ash/system/tray/tray_views.cc
diff --git a/ash/system/tray/tray_views.cc b/ash/system/tray/tray_views.cc
index 1c2e75ebdd3a30dfd57d512109a807eb4660facd..a39970961dbaa350a9cedbe584f829becd8fd938 100644
--- a/ash/system/tray/tray_views.cc
+++ b/ash/system/tray/tray_views.cc
@@ -73,6 +73,15 @@ void ActionableView::OnPaintFocusBorder(gfx::Canvas* canvas) {
   }
 }
 
+void ActionableView::GetAccessibleState(ui::AccessibleViewState* state) {
+  state->role = ui::AccessibilityTypes::ROLE_PUSHBUTTON;
+  state->name = accessible_name_;
+}
+
+void ActionableView::SetAccessibleName(const string16& name) {
+  accessible_name_ = name;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // HoverHighlightView