TimelineTextFilter.accept should checked only passed node

The filter shouldn't try to match regex against all descendants otherwise if a hiddent record matches all is ancestors will be revealed.

BUG=None

Review URL: https://codereview.chromium.org/250623002

git-svn-id: svn://svn.chromium.org/blink/trunk@172501 bbb929c8-8fbe-4397-9dbb-9b2b20218538