- Ensure that we use JSPRINCIPALS_DROP() where needed to avoid leaking principals.
- Clear newborn roots when we've finished with a JSContext, so we don't keep objects from being gc'd if there are no other references.
Part of bug 198655. Thanks to dbaron for much of the component loader patch. r=shaver, sr=brendan.
git-svn-id: svn://10.0.0.236/trunk@140093 18797224-902f-48f8-a5cc-f745e15eee43