In DeserializedClassDescriptor and MemberDeserializer, only the
`contextReceiverTypeList` field was used, and not
`contextReceiverTypeIdList` which is used when `-Xuse-type-table` is
enabled. The convention is to use a bunch of utilities declared in
`protoTypeTableUtil.kt` which deal with both methods of reading types.
Also, simplify the deserialization code in FIR (which was correct for
some reason).
Alexander Udalov