swift234

Stop recording protocol lists in nominal types.

The conformance lookup table is responsible for answering queries
about the protocols to which a particular nominal type conforms, so
stop storing (redundant and incorrect) protocol lists on the ASTs for
nominal types. Protocol types still store the list of protocols that
they inherit, however.

As a drive-by, stop lying about the number of bits that ProtocolDecl
uses on top of NominalTypeDecl, and move the overflow bits down into
ProtocolDecl itself so we don't bloat Decl unnecessarily.

Swift SVN r31381