[WIP] Try to re-enable .swiftinterface generation for stdlib.

Reproducer for https://bugs.swift.org/browse/TF-934:
run `validation-test/ParseableInterface/verify_stdlib.swift`.

Author: dan-zheng

validation-test/ParseableInterface/verify_stdlib.swift

@@ -1,10 +1,6 @@
 // Note that this test should still "pass" when Swift.swiftinterface has not
 // been generated.
 
-// SWIFT_ENABLE_TENSORFLOW
-// FIXME(TF-489): Re-enable this test after fixing `.swiftinterface` errors.
-// UNSUPPORTED: nonexecutable_test
-
 // RUN: %empty-directory(%t)
 // RUN: not ls %platform-module-dir/Swift.swiftmodule/%target-cpu.swiftinterface || %target-swift-frontend -build-module-from-parseable-interface %platform-module-dir/Swift.swiftmodule/%target-cpu.swiftinterface -parse-stdlib -o %t/Swift.swiftmodule