Don't send touch events to windows like menus when the touch occurs outside the menu bounds.

ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc

Index: ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
index 48368f962f2f3433b76c5ad20746ad28f135a481..8b1f178470d94acf43e64f2dca4e9800a8ae427f 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
@@ -96,8 +96,14 @@ DesktopWindowTreeHostWin::~DesktopWindowTreeHostWin() {
 
 // static
 aura::Window* DesktopWindowTreeHostWin::GetContentWindowForHWND(HWND hwnd) {
+  // All HWND's we create should have WindowTreeHost instances associated with
+  // them. There are exceptions like the content layer creating HWND's which
+  // are not associated with WindowTreeHost instances. In such cases we should
+  // try and find the WindowTreeHost associated with the parent.
   aura::WindowTreeHost* host =
       aura::WindowTreeHost::GetForAcceleratedWidget(hwnd);
+  if (!host)
+    host = aura::WindowTreeHost::GetForAcceleratedWidget(::GetParent(hwnd));
   return host ? host->window()->GetProperty(kContentWindowForRootWindow) : NULL;
 }