Fix Z-order for a bubble when it appears for inactive window.

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 0807934dbf915d60348559e88bf0fdcc5b9b5aae..a6072a9ed3de05f841d0ce4ca240c77cc111af9b 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
@@ -36,6 +36,7 @@
 #include "ui/views/widget/widget_hwnd_utils.h"
 #include "ui/views/win/fullscreen_handler.h"
 #include "ui/views/win/hwnd_message_handler.h"
+#include "ui/views/win/hwnd_util.h"
 #include "ui/wm/core/compound_event_filter.h"
 #include "ui/wm/core/input_method_event_filter.h"
 #include "ui/wm/core/window_animations.h"
@@ -230,6 +231,12 @@ void DesktopWindowTreeHostWin::SetSize(const gfx::Size& size) {
   message_handler_->SetSize(expanded);
 }
 
+void DesktopWindowTreeHostWin::StackAbove(aura::Window* window) {
+  HWND hwnd = HWNDForNativeView(window);
+  if (hwnd)
+    message_handler_->StackAbove(hwnd);
+}
+
 void DesktopWindowTreeHostWin::StackAtTop() {
   message_handler_->StackAtTop();
 }