RFR: 8246195: ListViewSkin/Behavior: misbehavior on switching skin

[Jeanette Winzenburg]

Cleanup memory leaks and malicious side-effects (produced by eventhandlers and listeners that were not removed) when
replacing a ListViewSkin.

The fix is to remove the listeners/handlers as needed. Added tests that failed before and pass after the fix.

It's part of the ongoing cleanup effort [JDK-8241364](https://bugs.openjdk.java.net/browse/JDK-8241364).

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Commit messages:
 - 8246195: ListViewSkin/Behavior: misbehavior on switching skin

Changes: https://git.openjdk.java.net/jfx/pull/247/files
 Webrev: https://webrevs.openjdk.java.net/jfx/247/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8246195
  Stats: 269 lines in 7 files changed: 252 ins; 9 del; 8 mod
  Patch: https://git.openjdk.java.net/jfx/pull/247.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/247/head:pull/247

PR: https://git.openjdk.java.net/jfx/pull/247