Make 'android' be an unrecognized keyword in TestExpectations.

Previously, it was a "macro" that would expand to 'icecreamsandwich'
and you'd then get an error complainig that 'icecreamsandwich' was
unrecognized, which was confusing.

R=ojan@chromium.org
BUG=256770

Review URL: https://chromiumcodereview.appspot.com/18205006

git-svn-id: svn://svn.chromium.org/blink/trunk@154269 bbb929c8-8fbe-4397-9dbb-9b2b20218538