This commit introduces some boilerplate for emitting warnings from the
AbuseFilter parser, and also code for showing these warnings in the ace
editor. Adding new warnings should be as simple as appending to
AbuseFilterParser::warnings (and adding the relevant i18n).
Bug: T264768
Bug: T269770
Change-Id: Ic11021b379f997a89f59c8c0572338d957e089a6
This is achieved by creating a new ParserStatus class. Aside from the
result of parse(), it contains whether the cache was warm. This can be
used to differentiate profiling data as part of T231112.
Another use case is returning non-fatal warnings (T269770).
Change-Id: Ifcbda861ce1a44bbe9bffba5b83cd9ef338a8dba
