XQuartz: Update window levels when changing rootless state

(cherry picked from commit 1359ded5bfc14a80fb998b01a54ecacb96c4ff88)

miext/rootless/rootless.h

@@ -57,6 +57,7 @@ typedef struct _RootlessWindowRec {
     int x, y;
     unsigned int width, height;
     unsigned int borderWidth;
+    int level;
 
     RootlessFrameID wid;	// implementation specific frame id
     WindowPtr win;		// underlying X window

miext/rootless/rootlessWindow.c

@@ -478,6 +478,7 @@ RootlessEnsureFrame(WindowPtr pWin)
     winRec->is_reorder_pending = FALSE;
     winRec->pixmap = NULL;
     winRec->wid = NULL;
+    winRec->level = 0;
 
     SETWINREC(pWin, winRec);