Bug 1319228 - Disable the js shell in tup automation builds. r=mshal

The js shell is symlinked back to the js objdir by a one off rule.
This fails in the current tup build because the symlink rule is
written in the Tupfile before the rule to build the shell.

MozReview-Commit-ID: 2FOv9FovXLm

--HG--
extra : rebase_source : de8dce6a1b50509b1d0da33eb7b6c35749269733

browser/config/mozconfigs/linux64/tup

@@ -13,4 +13,5 @@ export TUP=${TOOLTOOL_DIR}/tup/tup
 . "$topsrcdir/build/mozconfig.common.override"
 
 ac_add_options --enable-build-backends=Tup
+ac_add_options --disable-js-shell
 ac_add_options --upload-tup-db