Extend the hasPolicyWithRequireTrustedTypesForDirective boolean on
nsIContentSecurityPolicy to an enum in order to indicate whether there
is actually a require-trusted-types-for directive with "enforce"
disposition. Because there is currently only one sink group, we can
use this enum in GetTrustedTypesCompliantString() to determine whether
violations must be blocked, and perform violation reporting in an
independent function.
This will allow to make GetTrustedTypesCompliantString() work with
workers, by testing the enum on the worker thread and reporting
violations on the main thread.
Differential Revision: https://phabricator.services.mozilla.com/D233506
51c2edda75