telemetry: Remove workarounds for old reference builds in rendering benchmarks

R=tonyg@chromium.org
BUG=321819

Review URL: https://codereview.chromium.org/98053004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238659 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 238659