Adding sync_integration_tests to the chromeos_builder target.

Adding sync_integration_tests to the chromeos_builder target.
This will cause the sync_integration_tests to be built on the trybots,
however, they won't be run unless bot changes are made.

BUG=None
TEST=None
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=79053

[bradn, 2011-03-22 21:17:33]

This change http://codereview.chromium.org/6688045/ passed the trybots, even
though it would have failed if sync_integration_tests were built.

Turning them on.

[anna, 2011-03-22 22:08:11]

LGTM.