Fix use of uninitialized variable.

 src/xdisp.c (note_mouse_highlight): Initialize `part', to avoid a
 possible random value that matches one of those tested as
 condition to clear the mouse face.

src/ChangeLog

+2011-10-28  Eli Zaretskii  <eliz@gnu.org>
+
+	* xdisp.c (note_mouse_highlight): Initialize `part', to avoid a
+	possible random value that matches one of those tested as
+	condition to clear the mouse face.
+
 2011-10-28  Chong Yidong  <cyd@gnu.org>
 
 	* xdisp.c (note_mouse_highlight): Fix use of uninitialized var.

src/xdisp.c

@@ -26801,7 +26801,7 @@ void
 note_mouse_highlight (struct frame *f, int x, int y)
 {
   Mouse_HLInfo *hlinfo = MOUSE_HL_INFO (f);
-  enum window_part part;
+  enum window_part part = ON_NOTHING;
   Lisp_Object window;
   struct window *w;
   Cursor cursor = No_Cursor;