(PUP-514) Change warning to debug, and add validation of type expr

This changes the warning issued on the code path when a resource type
is required in order to do deserialization (apply phase). When this
happens on the server side (or during apply), the full source is
available, and the type in "known resource types" is loaded code that
may have typed parameters. This second time, no validation can and will
not take place because it is happening where there is no top scope
available. (This is fine, and should use result in a debug output).

This also fixes a couple of typos.