Protector: valid signatures are not updated during Web Data migration.

*) All Protector migrations are merged.
*) If a valid signature is present in pre-39 version table, it is not updated.
*) This also fixes http://crbug.com/115717


BUG=115717
TEST=WebDatabaseMigrationTest.*

Review URL: http://codereview.chromium.org/9600079

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@125423 0039d316-1c4b-4281-b951-d872f2087c98
5 files changed