[9] RFR (S) 8050173: Generalize BMH.copyWith API to all method handles

[Vladimir Ivanov]

>> http://cr.openjdk.java.net/~vlivanov/8050173/webrev.00/
>> https://bugs.openjdk.java.net/browse/JDK-8050173
>>
>> Added j.l.i.MethodHandle.copyWith(MethodType, LambdaForm) and provided implementation for all subclasses.
>>
>> Also, some cleanups:
>>   * rewrote MH.viewAsType on top of MH.copyWith;
>>   * extended MH.viewAsType to do strict checks w/ assertions turned on (new parameter: boolean strict);
>>   * extended MT.isViewableAs to accept both interface preserving and interface erasing conversions (new parameter: boolean keepInterfaces).
>>
>> Testing: jdk/java/lang/invoke, jdk/java/util/streams, nashorn, octane w/ "-ea -esa" and COMPILE_THRESHOLD={0,30}.
>>
>> Reviewed-by: vlivanov, ?
>> Contributed-by: john.r.rose at oracle.com
>>
>
> Looks good, just one comment.
>
> MethodHandles.restrictReceiver
>
> This method has:
>
> 1578         private MethodHandle restrictReceiver(MemberName method, MethodHandle mh, Class<?> caller) throws IllegalAccessException {
> ...
> 1589             assert(mh instanceof DirectMethodHandle);  // DirectMethodHandle.copyWith
>
> Why not make the second parameter be "DirectMethodHandle mh" ?
Good point! While prototyping this I spotted uncovered corner case 
(restrict a receiver on a MH with bound caller).

Updated webrev:
   http://cr.openjdk.java.net/~vlivanov/8050173/webrev.01/
Diff:
   http://cr.openjdk.java.net/~vlivanov/8050173/webrev.00.01/

Reordered restrictReceiver and maybeBindCaller operations.

Best regards,
Vladimir Ivanov