Fix check for a date with a 24th hour

Fix check for a date with a 24th hour

According to the ECMA spec, a 24th hour is allowed if the minutes, seconds, and milliseconds are all zero (i.e. it's midnight). Previously, we parsed the date correctly, however, we failed to account in all checks for the possibility of a 24th hour. This CL changes the check to allow a 24th hour if it's exactly midnight.

BUG=chromium:174609
LOG=Y

Review URL: https://codereview.chromium.org/1240093005

Cr-Commit-Position: refs/heads/master@{#29816}