(PUP-798) E4ParserAdapter watches files through Environment

Instead of passing known_resource_types, if present, pass the given
environment, and provide a delegate method to watch_file on Environment.
Clears up a few layers of type checking and does not require the adapter
to know anything about known_resource_types for the purpose of watching
files, but a valid environment must be passed.
(maint) Uniform use of TypeCollectionHelper in Scope

Scope includes TypeCollectionHelper which provides an accessor for
known_resource_types.  This patch just fixes a direct reference to
environment.known_resource_types to instead use the delegate method the
same as other known_resource_types calls in the Scope class.