mash: Migrate ShelfTooltipManager to wm common types.

ash/mus/bridge/wm_window_mus.cc

Index: ash/mus/bridge/wm_window_mus.cc
diff --git a/ash/mus/bridge/wm_window_mus.cc b/ash/mus/bridge/wm_window_mus.cc
index c635a13f5de99d9f68ac77d30d80d67667cfde0f..6a2f764dca1cc4ba25af4a7005e6e2d197882236 100644
--- a/ash/mus/bridge/wm_window_mus.cc
+++ b/ash/mus/bridge/wm_window_mus.cc
@@ -19,6 +19,7 @@
 #include "services/ui/public/cpp/window_tree_client.h"
 #include "services/ui/public/interfaces/window_manager.mojom.h"
 #include "ui/aura/mus/mus_util.h"
+#include "ui/aura/window.h"
 #include "ui/base/hit_test.h"
 #include "ui/display/display.h"
 #include "ui/views/view.h"
@@ -739,6 +740,14 @@ bool WmWindowMus::HasObserver(const WmWindowObserver* observer) const {
   return observers_.HasObserver(observer);
 }
 
+void WmWindowMus::AddLimitedPreTargetHandler(ui::EventHandler* handler) {
+  widget_->GetNativeWindow()->AddPreTargetHandler(handler);

[msw, 2016/07/25 22:56:44]

q: Should this use GetInternalWidget (and bail if null)? Something else?

[sky, 2016/07/26 13:25:20]

It's possible to make the non-internal widget case work, but we can figure that
out later if necessary. How about extending the comment in
AddLimitedPreTargetHandler to indicate only for windows associated with a widget
and a DCHECK(GetInternalWidget()) ?

[msw, 2016/07/26 17:43:25]

Done.

+}
+
+void WmWindowMus::RemoveLimitedPreTargetHandler(ui::EventHandler* handler) {
+  widget_->GetNativeWindow()->RemovePreTargetHandler(handler);
+}
+
 void WmWindowMus::OnTreeChanging(const TreeChangeParams& params) {
   WmWindowObserver::TreeChangeParams wm_params;
   wm_params.target = Get(params.target);