Change visibility of some linter methods

Summary: Change the visibility of the raiseLintAtSomething methods, mainly to allow linter rules to raise linter messages (see D10541).

Test Plan: arc unit

Reviewers: Blessed Reviewers, epriestley

Reviewed By: Blessed Reviewers, epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D12976