Fix test for "last updated" text.

The minutes field was updated to be zero-padded, but the test wasn't, so the
test would fail at certain times of day. This updates that test to always pass.

NOTRY=true

Review URL: https://codereview.chromium.org/473433002

git-svn-id: svn://svn.chromium.org/blink/trunk@180231 bbb929c8-8fbe-4397-9dbb-9b2b20218538