Add protection against a null LocalSiteProfile.permissions.
Add protection against a null LocalSiteProfile.permissions.

It appears that it's possible a LocalSiteProfile.permissions to be None,
and in this case, permission lookups will fail. We're now more careful
about this, and default it to {} when processing.

KnowNo/reviewboard,davidt/reviewboard,davidt/reviewboard,custode/reviewboard,1tush/reviewboard,sgallagher/reviewboard,sgallagher/reviewboard,reviewboard/reviewboard,davidt/reviewboard,beol/reviewboard,sgallagher/reviewboard,KnowNo/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard,1tush/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard,chipx86/reviewboard,brennie/reviewboard,1tush/reviewboard,KnowNo/reviewboard,beol/reviewboard,1tush/reviewboard,1tush/reviewboard,brennie/reviewboard,chipx86/reviewboard,davidt/reviewboard,1tush/reviewboard,beol/reviewboard,custode/reviewboard,reviewboard/reviewboard,brennie/reviewboard,chipx86/reviewboard,bkochendorfer/reviewboard,brennie/reviewboard,KnowNo/reviewboard,reviewboard/reviewboard,custode/reviewboard,custode/reviewboard,beol/reviewboard,sgallagher/reviewboard,reviewboard/reviewboard,chipx86/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard