Rendering text-justify:none

When the value of text-justify is 'none',
we don't need to touch anything related to the expansion opportunity.
We just need to leave the expansion opportunity as 0,
so that justification doesn't work for this case.

BUG=248894

Review URL: https://codereview.chromium.org/50413008

git-svn-id: svn://svn.chromium.org/blink/trunk@161006 bbb929c8-8fbe-4397-9dbb-9b2b20218538