Ignore tests on Android correctly
auto merge of #9698 : sanxiyn/rust/android, r=huonw
Rewrite lint passes with less visitor cruft

This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.

Closes #8589
auto merge of #9686 : alexcrichton/rust/lint, r=thestinger

This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.

Closes #8589
extra: remove unnecessary second level functions

do_strptime() and do_strftime()