RFR: JDK-8287094: IGV: show node input numbers in edge tooltips [v2]

[Tobias Holenstein]

> For nodes with many inputs, such as safepoints, it is difficult and error-prone to figure out the exact input number of a given incoming edge. 
> 
> Extend the Edge Tooltips to include the input number of the destination node:
> **Before** `91 Addl -> 92 SafePoint`
> **Now** `91 Addl -> 92 SafePoint [NR]`
> ![edge](https://urldefense.com/v3/__https://user-images.githubusercontent.com/71546117/175506945-6f5137d2-7647-4acb-a135-8fcb719df3e6.png__;!!ACWV5N9M2RV99hQ!L8ubNbTpCkj1YtX5aazQ4WUnHvsQHZMDQZfVz_r_3U2Yt_ebCOiJFG13m5ocQrDwFppD2y4lyGVpRdqGKJFbklAiBQL8v6VIVXEM$ )

Tobias Holenstein has updated the pull request incrementally with one additional commit since the last revision:

  CustomSelectAction added

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9273/files
  - new: https://git.openjdk.org/jdk/pull/9273/files/b3df3367..7bc37589

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9273&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9273&range=00-01

  Stats: 67 lines in 1 file changed: 67 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/9273.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9273/head:pull/9273

PR: https://git.openjdk.org/jdk/pull/9273