TimelinePanel: REGRESSION search doesn't work if focus not in records view.

BUG=
R=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/225113003

git-svn-id: svn://svn.chromium.org/blink/trunk@171481 bbb929c8-8fbe-4397-9dbb-9b2b20218538