[gnome-chess/gnome-3-36] scene: fix attempt to remove invalid source

[Michael Catanzaro <mcatanzaro src gnome org>]

commit b0f12ebc0a55bc937f8e80a8ef76ec36a336901d
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Wed Oct 14 15:14:13 2020 +0000

    scene: fix attempt to remove invalid source
    
    Fixes:
    
    0  _g_log_abort (breakpoint=1) at ../../../../Projects/glib/glib/gmessages.c:559
    1  0x00007f4cae0bf45e in g_logv (log_domain=0x7f4cae122b50 "GLib", log_level=G_LOG_LEVEL_CRITICAL,
        format=0x7f4cae122fc0 "Source ID %u was not found when attempting to remove it", args=0x7ffdd5eff9b8)
        at ../../../../Projects/glib/glib/gmessages.c:1405
    2  0x00007f4cae0bf54f in g_log (log_domain=0x7f4cae122b50 "GLib", log_level=G_LOG_LEVEL_CRITICAL,
        format=0x7f4cae122fc0 "Source ID %u was not found when attempting to remove it")
        at ../../../../Projects/glib/glib/gmessages.c:1447
    3  0x00007f4cae0b4524 in g_source_remove (tag=2921) at ../../../../Projects/glib/glib/gmain.c:2499
    4  0x000000000041958e in chess_scene_set_game (self=0x25a0150, value=0x27024e0)
        at ../../../../Projects/gnome-chess/src/chess-scene.vala:97
    5  0x0000000000423db6 in chess_application_start_game (self=0x22b2320)
        at ../../../../Projects/gnome-chess/src/gnome-chess.vala:520
    6  0x00000000004341f0 in chess_application_start_new_game (self=0x22b2320)
        at ../../../../Projects/gnome-chess/src/gnome-chess.vala:2464
    7  0x000000000042afac in chess_application_new_game_cb (self=0x22b2320)
        at ../../../../Projects/gnome-chess/src/gnome-chess.vala:1519
    
    
    (cherry picked from commit b9d02fe1fcdd4d3b394d78443c8744a3ea20a95e)

 src/chess-scene.vala | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/chess-scene.vala b/src/chess-scene.vala
index 76630e7..35f25ec 100644
--- a/src/chess-scene.vala
+++ b/src/chess-scene.vala
@@ -372,6 +372,7 @@ public class ChessScene : Object
             return Source.CONTINUE;
 
         game.remove_hold ();
+        animate_timeout_id = 0;
         return Source.REMOVE;
     }
 }