Improve previous change for tool bar image support on GTK+2 with cairo

* src/gtkutil.c (xg_get_pixbuf_from_surface) [USE_CAIRO && !HAVE_GTK3]: Remove
unused argument f.  All callers changed.  Handle general alpha value.
1 job for master in 55 minutes and 17 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
failed #1935
test-all

00:55:17

 
Name Stage Failure
failed
test-all Test
make[2]: *** [check-doit] Error 1
Makefile:318: recipe for target 'check-doit' failed
make[2]: Leaving directory '/builds/emacs/emacs/test'
Makefile:293: recipe for target 'check-expensive' failed
make[1]: *** [check-expensive] Error 2
make[1]: Leaving directory '/builds/emacs/emacs/test'
Makefile:957: recipe for target 'check-expensive' failed
make: *** [check-expensive] Error 2
ERROR: Job failed: exit code 1