A couple of tests are expecting merge-modules behaviour,
add `-no-emit-module-separately` in those cases to
ensure that merge modules is used in both the old
and new driver.
Raw values of enum cases from another module are not specified in the declaration of the enum unless that enum is `@objc`. This meant that `EnumRawValuesRequest` was computing potentially incorrect raw values when the enum declaration supported it and was emitting incorrect diagnostics for other enum decls.
Resolves SR-14355 and rdar://75451691
The `-force-single-frontend-invocation` flag predates WMO and is now an
alias for `-whole-module-optimization`. We should use the latter and let
the former fade into history.
