master f720630195: Remove excessive synchronization from x_sync_with_move

[Po Lu]

branch: master
commit f720630195357440af179607aa74e8ed14a58e83
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Remove excessive synchronization from x_sync_with_move
    
    * src/xterm.c (x_sync_with_move): Remove redundant XSync.  The X
    server always handles requests in order.
---
 src/xterm.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index 2067e8bb74..7b4a65e87f 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -25055,11 +25055,9 @@ x_sync_with_move (struct frame *f, int left, int top, 
bool fuzzy)
       current_left = 0;
       current_top = 0;
 
-      /* In theory, this call to XSync only needs to happen once, but in
-         practice, it doesn't seem to work, hence the need for the surrounding
-         loop.  */
-
-      XSync (FRAME_X_DISPLAY (f), False);
+      /* There is no need to call XSync (even when no window manager
+        is present) because x_real_positions already does that
+        implicitly.  */
       x_real_positions (f, &current_left, &current_top);
 
       if (fuzzy)