Enums without an explicit, fixed, underlying type are implicitly given a
fixed 'int' type for ABI compatibility with MSVC. However, we can
enforce the standard-mandated rules on these types as-if we didn't know
this fact if the tag is not part of a definition.
llvm-svn: 249667
These test updates almost exclusively around the change in behavior
around enum: enums without a definition are considered incomplete except
when targeting MSVC ABIs. Since these tests are interested in the
'incomplete-enum' behavior, restrict them to %itanium_abi_triple.
llvm-svn: 249660