master b5b6159d03: Fix potential crash with fast mouse position enabled

[Po Lu]

branch: master
commit b5b6159d036fd167c6cab21532c2fdd587051d28
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix potential crash with fast mouse position enabled
    
    * src/xterm.c (x_free_frame_resources): Clear
    last_mouse_motion_frame and last_mouse_frame if required.
---
 src/xterm.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/xterm.c b/src/xterm.c
index 8d8b0a0c0a..028bb7582c 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -28841,6 +28841,13 @@ x_free_frame_resources (struct frame *f)
   if (f == hlinfo->mouse_face_mouse_frame)
     reset_mouse_highlight (hlinfo);
 
+  /* These two need to be freed now that they are used to compute the
+     mouse position, I think.  */
+  if (f == dpyinfo->last_mouse_motion_frame)
+    dpyinfo->last_mouse_motion_frame = NULL;
+  if (f == dpyinfo->last_mouse_frame)
+    dpyinfo->last_mouse_frame = NULL;
+
 #ifdef HAVE_XINPUT2
   /* Consider a frame being unfocused with no following FocusIn event
      while an older focus from another seat exists.  The client