mash: Migrate ShelfTooltipManager to wm common types.

ash/aura/wm_window_aura.cc

Index: ash/aura/wm_window_aura.cc
diff --git a/ash/aura/wm_window_aura.cc b/ash/aura/wm_window_aura.cc
index f3345f9b71b796f7996e6e73f0d8c68021806c76..82a18dd4ab68793f972c2539c234b87964839341 100644
--- a/ash/aura/wm_window_aura.cc
+++ b/ash/aura/wm_window_aura.cc
@@ -662,6 +662,15 @@ bool WmWindowAura::HasObserver(const WmWindowObserver* observer) const {
   return observers_.HasObserver(observer);
 }
 
+void WmWindowAura::AddLimitedPreTargetHandler(ui::EventHandler* handler) {
+  // This behaves differently from WmWindowMus for child and embedded windows.
+  window_->AddPreTargetHandler(handler);
+}
+
+void WmWindowAura::RemoveLimitedPreTargetHandler(ui::EventHandler* handler) {
+  window_->RemovePreTargetHandler(handler);
+}
+
 void WmWindowAura::OnWindowHierarchyChanging(
     const HierarchyChangeParams& params) {
   WmWindowObserver::TreeChangeParams wm_params;