Timeline: [REGRESSION] windowFilter should be updated when we hit into visible rows limit.

Also we have to reset it when we start new recording session.

It was regressed in r163960

BUG=

Review URL: https://codereview.chromium.org/119083002

git-svn-id: svn://svn.chromium.org/blink/trunk@164165 bbb929c8-8fbe-4397-9dbb-9b2b20218538