DevTools: bump timeline bar height 1px
DevTools: bump timeline bar height 1px

Review URL: https://codereview.chromium.org/14462004

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@149325 bbb929c8-8fbe-4397-9dbb-9b2b20218538

primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs