RFR: 8308097: Generational ZGC: Update constructor syntax

[Stefan Karlsson]

ZGC's current constructor syntax works well with some editors, but not all. There is a wish to move over from the current syntax:


ZClass:ZClass() :
    ZSuper(),
    _member0,
    _member1 {
  // Code
  doit();
}


to the following syntax:

ZClass:ZClass()
  : ZSuper(),
    _member0,
    _member1 {
  // Code
  doit();
}


I propose that make this change.

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

Commit messages:
 - 8308097: Generational ZGC: Update constructor syntax

Changes: https://git.openjdk.org/jdk/pull/13987/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13987&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8308097
  Stats: 622 lines in 95 files changed: 8 ins; 17 del; 597 mod
  Patch: https://git.openjdk.org/jdk/pull/13987.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13987/head:pull/13987

PR: https://git.openjdk.org/jdk/pull/13987