Merge lp:~darkxst/overlay-scrollbar/lp1386255 into lp:overlay-scrollbar

[Tim Lunn]

Check for null grab_notify handler before hijacking it. This fixes a crash in GTK+3.14 where grab_notify is no longer used, Thanks Marius Gedminas for the fix!

[Lars Karlitski (larsu)]

We might want to check the other functions for NULL as well at some point. But this won't happen for 3.14 and the longevity of this module is questionable, so let's go with this.

Thanks for the fix!

review: Approve

=== modified file 'os/os-scrollbar.c'
--- os/os-scrollbar.c	2014-06-09 03:50:50 +0000
+++ os/os-scrollbar.c	2014-10-28 23:19:32 +0000
@@ -4166,7 +4166,8 @@
   if (widget_class->state_changed == pre_hijacked_scrollbar_state_changed)
     widget_class->state_changed = hijacked_scrollbar_state_changed;
 #endif
-  if (widget_class->grab_notify == pre_hijacked_scrollbar_grab_notify)
+  if (pre_hijacked_scrollbar_grab_notify &&
+      widget_class->grab_notify == pre_hijacked_scrollbar_grab_notify)
     widget_class->grab_notify = hijacked_scrollbar_grab_notify;
   if (widget_class->hide == pre_hijacked_scrollbar_hide)
     widget_class->hide = hijacked_scrollbar_hide;