Frontend: Really allow any experimental feature when compiling a module interface

[tshortli]

The fix for #72632 was not sufficient because when modules are built from textual interface that happens in a sub-invocation which does not have typecheck-from-interface or compile-from-interface requested action. Instead of checking a requested action, set a language option to control whether non-production experimental features are allowed.

Resolves rdar://125561443

[tshortli]

@swift-ci please smoke test

[drodriguez]

Can you add a REQUIRES: asserts in test/ModuleInterface/ExperimentalFeatures.swiftinterface that was modified in #72632 ?

Otherwise it fails if one tries to run the tests in a noasserts compiler with:

<unknown>:0: error: unexpected error produced: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler
<unknown>:0: error: diagnostic produced elsewhere: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler

[tshortli]

Can you add a REQUIRES: asserts in test/ModuleInterface/ExperimentalFeatures.swiftinterface that was modified in #72632 ?

Otherwise it fails if one tries to run the tests in a noasserts compiler with:

<unknown>:0: error: unexpected error produced: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler
<unknown>:0: error: diagnostic produced elsewhere: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler

This PR is fixing that issue you're reporting. Adding REQUIRES: asserts would defeat the purpose of the test; it is meant to validate that the test works in no_asserts, I just didn't accomplish that correctly on the first try.

[drodriguez]

Sorry then, I misunderstood how the fix worked.

[FouadMagdy01]

Can you add a REQUIRES: asserts in test/ModuleInterface/ExperimentalFeatures.swiftinterface that was modified in #72632 ?
Otherwise it fails if one tries to run the tests in a noasserts compiler with:

<unknown>:0: error: unexpected error produced: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler
<unknown>:0: error: diagnostic produced elsewhere: experimental feature 'ParserRoundTrip' cannot be enabled in production compiler

This PR is fixing that issue you're reporting. Adding REQUIRES: asserts would defeat the purpose of the test; it is meant to validate that the test works in no_asserts, I just didn't accomplish that correctly on the first try.

How did you solve this
I get this issue
<unknown>:0: experimental feature 'OpaqueTypeErasure' cannot be enabled in a production compiler