Use gjs_context_get_native_context()

[Michael Higgins <linux evolone org>]

http://git.gnome.org/browse/gnome-shell/commit/?id=1f1f4432f6fa9a0ed510caeb87772786b3b6d02c

... *appeared* to have broken my builds like this: 

shell-global.c: In function 'shell_global_add_extension_importer':
shell-global.c:618: error: implicit declaration of function
'gjs_context_get_native_context' shell-global.c:618: error:
initialization makes pointer from integer without a cast
shell-global.c: In function 'shell_global_gc': shell-global.c:809:
error: initialization makes pointer from integer without a cast

The fix *seems to be* to set --enable-compile-warnings to something...
which I didn't need, I guess, before this revision. I could be totally
wrong too, been messing with this since I updated this morning.

Anyway, I'm hooked. Go gnome-shell!

Cheers,

-- 
 |\  /|        |   |          ~ ~  
 | \/ |        |---|          `|` ?
 |    |ichael  |   |iggins    \^ /
 michael.higgins[at]evolone[dot]org