As people have been raising the unit test coverage, we should make sure
we're raising the thresholds as well. This keeps the new code from
being lax in coverage.
The metric used here was to set whole number percentage points that were
more than one-half of a percentage point below the actual coverage.
Change-Id: I348d4b8cafcf6c7d0dc8e770b66609984e89c20b
Partial-Bug: 1506891