[lworld] RFR: 8378672: [lworld] Consolidate a factory to create a GraphKit from a SafePointNode [v3]

[Quan Anh Mai]

> Hi,
> 
> I find it is a common occurrence that we want to expand a `SafePointNode` into a subgraph, and to do that we may need to create a `JVMState` ourselves, which may easily results in cumbersome errors because the kit state is not created properly. I tried using `GraphKit` to expand generate code after a `SafePointNode` (in particular, I tried to emit an uncommon trap there), which leads to this PR which consolidates the creation of a `GraphKit` from a `SafePointNode` that we want to use its debug state.
> 
> Please take a look and leave your reviews, thanks a lot.

Quan Anh Mai has updated the pull request incrementally with one additional commit since the last revision:

  only add to the worklist with igvn

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

Changes:
  - all: https://git.openjdk.org/valhalla/pull/2163/files
  - new: https://git.openjdk.org/valhalla/pull/2163/files/8c50fec9..aeafd1df

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=2163&range=02
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=2163&range=01-02

  Stats: 9 lines in 2 files changed: 4 ins; 1 del; 4 mod
  Patch: https://git.openjdk.org/valhalla/pull/2163.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2163/head:pull/2163

PR: https://git.openjdk.org/valhalla/pull/2163