RFR: 8254269: simplify Node::disconnect_inputs [v3]

[Xin Liu]

> 8254269: simplify Node::disconnect_inputs

Xin Liu has updated the pull request incrementally with one additional commit since the last revision:

  8254269: simplify Node::disconnect_inputs

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/589/files
  - new: https://git.openjdk.java.net/jdk/pull/589/files/b8a72755..5c6bb10a

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=589&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=589&range=01-02

  Stats: 13 lines in 1 file changed: 0 ins; 8 del; 5 mod
  Patch: https://git.openjdk.java.net/jdk/pull/589.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/589/head:pull/589

PR: https://git.openjdk.java.net/jdk/pull/589