TimelineFlameChart: process new records incrementally.
TimelineFlameChart: process new records incrementally.

BUG=
R=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/186553002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@168387 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