Fixed locale test in the presence of LANGUAGE

According to GNU documents, the priority order of language variables
is LANGUAGE, LC_ALL, LC_*, LANG. Therefore, if LANGUAGE is set, it
overrides the LC_ALL setting from the test. An empty value is ignored,
and setting it to empty is easier to deal with than just deleting the
variable.

Also fixed the Google translate fail esperanto grammar.

Fixes bug 1235058

Change-Id: Ic97b90dfc21997e19cc473250794a9b3c526beb5
Merge "Fixed locale test in the presence of LANGUAGE"