RFR: 8277848 Binding and Unbinding to List leads to memory leak

[Florian Kirmaier]

Making the initial listener of the ListProperty weak fixes the problem.
The same is fixed for Set and Map.
Due to a smart implementation, this is done without any performance drawback.
(The trick is to have an object, which is both the WeakReference and the Changelistener)
By implying the same trick to the InvalidationListener, this should even improve the performance of the collection properties.

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Commit messages:
 - JDK-8277848

Changes: https://git.openjdk.java.net/jfx/pull/689/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=689&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8277848
  Stats: 157 lines in 6 files changed: 122 ins; 12 del; 23 mod
  Patch: https://git.openjdk.java.net/jfx/pull/689.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/689/head:pull/689

PR: https://git.openjdk.java.net/jfx/pull/689