Fix #4906: cache the roles array in the user info object.

[zyhfish]

Fix #4906.

[valadas]

Makes sense to me

[bdukes]

How does this cache get cleared if the roles were to change?

[abner-diaz]

Hi -- I work for the client that request this patch as a result of our internal load testing. I think the wording cache is not as accurate it just being a private member in the class.

The UserInfo class is CacheLevel.notCacheable, so it's lifecycle seems limited to a request. Also, the code pattern used in the Roles get accessor was taken from the Membership get accessor. So any issues with cache refresh or stale data would also occur there (since that is also likely to change). That is unlikely because the UserInfo class does not seem targeted for caching.

[zyhfish]

How does this cache get cleared if the roles were to change?

Hi @bdukes , the Roles info is calculated from Social.Roles property that is saved in a private field as well, so it should be good enough to store in a private field for it.

[valadas]

Sounds good to me... @bdukes you are fine with merging this ?