Revert 245748 "[Telemetry] Properly handle retries after browser..."

This seems to have broken all of the chromium.gpu bots. Reverting.

> [Telemetry] Properly handle retries after browser crash.
> 
> Previously it was easy for the results to get into a bad state and assert in a
> variety of ways.
> 
> This ensures we ignore the partial results in the case of a crash.
> 
> BUG=
> 
> Review URL: https://codereview.chromium.org/140773004

TBR=tonyg@chromium.org

Review URL: https://codereview.chromium.org/142383002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245769 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245769