Bug 1451065 - Install Python 3 on Arch; r=mshal

MozReview-Commit-ID: Gg7gn72Xev9

--HG--
extra : rebase_source : c61fca33e29721b6a6f7c1281186f6935da193b7

python/mozboot/mozboot/archlinux.py

@@ -23,6 +23,7 @@ class ArchlinuxBootstrapper(StyloInstall, BaseBootstrapper):
         'nodejs',
         'python2',
         'python2-setuptools',
+        'python',  # This is Python 3 on Arch.
         'unzip',
         'zip',
     ]