PyAutoPerfTests: Pass additional flags for PGO.
PyAutoPerfTests: Pass additional flags for PGO.

These flags are required to dump PGO (profile-guided-optimization) data for
Chrome.

BUG=none
TEST=USE_PGO=1 python chrome/test/functional/<name>.py
Made sure Chrome ran with --renderer-clean-exit and --no-sandbox.


Review URL: http://codereview.chromium.org/10115006

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@132908 0039d316-1c4b-4281-b951-d872f2087c98

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