This patch does a few things:
1) It removes the symantecRoot and symantec_affected certs from build/pgo/certs'
   DB.
2) It upgrades that DB from the old format to SQLite (and this 8/3 to 9/4).
3) It adds a new cert "imminently_distrusted" to that DB for the bc test.
4) It changes the Subject of the immient distrust test to only have the CN
   field: this is because certutil reorders C to come after CN, and just like
   with the real Symantec certs, I had put C first. So rather than deal with
   importing the end entity for the pgo tests, I decided to just make things
   simple and change the tested subject.
5) Finally, it re-enables the test that was disabled in Bug 1434300.

MozReview-Commit-ID: Bt2RKyInJje

--HG--
rename : build/pgo/certs/cert8.db => build/pgo/certs/cert9.db
rename : build/pgo/certs/key3.db => build/pgo/certs/key4.db
extra : rebase_source : efceb67ae16f0af617bbd8bec201d52eee0f467d