Revert of Move counters update into a sepearate event (https://codereview.chromium.org/237003002/)

Reason for revert:
Broke layout tests.

Original issue's description:
> Move counters update into a sepearate event
> 
> Counter updates are sent as sepearate events. This allows to simplify timeline model on the front-end side and will simplify switching timeline to the trace events.
> 
> Removed JS heap counters from regular events. JS heap size changes for selected event are not shown except for GCEvent, instead new heap size graph is added to the memory view.
> 
> BUG=361045
> R=pfeldman@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=171555

TBR=alph@chromium.org,loislo@chromium.org,pfeldman@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=361045

Review URL: https://codereview.chromium.org/238913002

git-svn-id: svn://svn.chromium.org/blink/trunk@171558 bbb929c8-8fbe-4397-9dbb-9b2b20218538