[lworld] RFR: 8358777: [lworld] Allow explicit super invocation in canonical constructors [v3]

[Vicente Romero]

> This is the implementation of section `Record class constructors` of JEP 401, see [1]. This PR allows a normal canonical constructor for a record class to contain an explicit 'super()' call, expressing an explicit division between early and late construction. Same applies to identity record classes
> 
> [1] https://bugs.openjdk.org/browse/JDK-8317277
> 
> Note: this PR depends on flexible constructor bodies, given that the change that makes it a final feature is not merged in lworld yet I will wait for that to happen to do a merge and then push this fix

Vicente Romero has updated the pull request incrementally with one additional commit since the last revision:

  addressing review comments

-------------

Changes:
  - all: https://git.openjdk.org/valhalla/pull/1483/files
  - new: https://git.openjdk.org/valhalla/pull/1483/files/d470cc29..674dbeb2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=1483&range=02
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=1483&range=01-02

  Stats: 12 lines in 2 files changed: 3 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/valhalla/pull/1483.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1483/head:pull/1483

PR: https://git.openjdk.org/valhalla/pull/1483