[code-reflection] RFR: Drop support for quoted structural lambdas [v2]

[Paul Sandoz]

On Thu, 6 Nov 2025 15:29:20 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> The Babylon compiler extension supports structural quoting of lambdas. That is, if a lambda expression has `Quoted` target, then it must have explicit parameter types, and must be type-checked bottom up:
>> 
>> 
>> Quoted q = () ->  {}
>> 
>> 
>> Historically, `Quoted` was the first way to model quotable lambda expressions, and the language changes to support structural quotable lambdas were fairly invasive. Since then we moved to a more minimalistic approach which is similar to what we do for serializable lambdas: we use an intersection type cast to force quotability of the lambda expression:
>> 
>> 
>> Runnable r = (Runnable & Quotable)() ->  {}
>> 
>> 
>> Since the surface area of the `Quotable` support is much smaller (it shares the same machinery already available for serializable lambdas), it would be better to remove support for Quoted target when moving towards incubation.
>> 
>> This PR fixes all existing tests in langtools/JDK to use `Quotable` instead of `Quoted`. I did **not** check HAT, or `cr-examples`.
>
> Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Re-add accidentally deleted test

Marked as reviewed by psandoz (Lead).

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PR Review: https://git.openjdk.org/babylon/pull/667#pullrequestreview-3430367202