DevTools: skip animation when resetting Timeline flame chart to initial state

Animation will break if endTime is Infinity which is the case when we reset Timeline flame chart time window to initial range [0, Infinity)

BUG=424506

Review URL: https://codereview.chromium.org/664693003

git-svn-id: svn://svn.chromium.org/blink/trunk@183965 bbb929c8-8fbe-4397-9dbb-9b2b20218538