Make the GN use_glib argument not user-selectable.
Make the GN use_glib argument not user-selectable.

The interaction between use_ozone and use_glib was
awkward when they were both declared as GN arguments,
and there doesn't seem to be a good reason for
use_glib to be user-togglable.

R=brettw@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1170873003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#333544}

chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,chuan9/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,hgl888/chromium-crosswalk,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,chuan9/chromium-crosswalk,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,Just-D/chromium-1,hgl888/chromium-crosswalk,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,hgl888/chromium-crosswalk,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,Just-D/chromium-1,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,hgl888/chromium-crosswalk,chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium