RFR: 8301858: Verification error when compiling switch with record patterns [v3]

[Aggelos Biboudis]

> When unrolling/translating record patterns with an unconditional case, we were translating the last/innermost case to`case null, default` skipping the initialization of a bound variable `o` in the example below:
> 
>     switch (..) {
>       case R1(Object o):
>                       return meth_O(o); 
>     }
>     => 
>     switch (..) {
>        case R1: 
>           switch(..) {
>             case null, default:
>                             return meth_O(o);
>           }
>     }
> 
> This PR addresses that by emitting the correct label instead of default.

Aggelos Biboudis has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:

  Fix unrolling with cases that have null and unconditional
  
  Co-authored-by: Jan Lahoda <jan.lahoda at oracle.com>

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12438/files
  - new: https://git.openjdk.org/jdk/pull/12438/files/f9d51d99..e77384cd

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12438&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12438&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/12438.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12438/head:pull/12438

PR: https://git.openjdk.org/jdk/pull/12438