Fix crash in CLM.

A RELEASE_ASSERT is being triggered due to not having up-to-date
values in CLM::doPaintTask(). This should ensure that the values
are updated properly.

BUG=413356

Review URL: https://codereview.chromium.org/585553002

git-svn-id: svn://svn.chromium.org/blink/trunk@182269 bbb929c8-8fbe-4397-9dbb-9b2b20218538