Steps to reproduce: 1) Record timeline 2) Select small range with left tick close to zero 3) Move pointer to the right end of the ruler 4) Zoom-in with mouse-wheel Result: right tick goes below the zero.
Created attachment 149147 [details] Patch
Comment on attachment 149147 [details] Patch LGTM
Created attachment 149150 [details] Patch
Committed r121084: <http://trac.webkit.org/changeset/121084>
Comment on attachment 149150 [details] Patch Clearing r? to remove the bug from the request queue.