[gimp] Issue #7843: Middle clicking while manipulating canvas with spacebar…

[Jehan <jehanp src gnome org>]

commit 7ca324fb2d97ad821839abae0cee3e4012d19704
Author: Jehan <jehan girinstud io>
Date:   Fri Mar 25 23:02:07 2022 +0100

    Issue #7843: Middle clicking while manipulating canvas with spacebar…
    
    … causes failed assertion.

 app/display/gimpdisplayshell-tool-events.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/app/display/gimpdisplayshell-tool-events.c b/app/display/gimpdisplayshell-tool-events.c
index 487a95a158..e28e7199f7 100644
--- a/app/display/gimpdisplayshell-tool-events.c
+++ b/app/display/gimpdisplayshell-tool-events.c
@@ -700,7 +700,10 @@ gimp_display_shell_canvas_tool_events (GtkWidget        *canvas,
           }
         else if (bevent->button == 2)
           {
-            if (shell->scrolling)
+            if (shell->scrolling                 &&
+                ! shell->button1_release_pending &&
+                (! shell->space_release_pending ||
+                 shell->display->config->space_bar_action != GIMP_SPACE_BAR_ACTION_PAN))
               gimp_display_shell_stop_scrolling (shell, event);
           }
         else if (bevent->button == 3)