[Rev 03] RFR: 8237372: NullPointerException in TabPaneSkin.stopDrag

[Robert Lichtenberger]

> Test simulates a single mouse-released event.
> Fix simply guards against the null case.

The pull request has been updated with 1 additional commit.

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Added commits:
 - 39a61821: 8237372: NullPointerException in TabPaneSkin.stopDrag

Changes:
  - all: https://git.openjdk.java.net/jfx/pull/89/files
  - new: https://git.openjdk.java.net/jfx/pull/89/files/a54a5306..39a61821

Webrevs:
 - full: https://webrevs.openjdk.java.net/jfx/89/webrev.03
 - incr: https://webrevs.openjdk.java.net/jfx/89/webrev.02-03

  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.java.net/jfx/pull/89.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/89/head:pull/89

PR: https://git.openjdk.java.net/jfx/pull/89