Small fix to clear a reference to a removed node left by Scene$MouseHandler.
------------- Commit messages: - 8264330: Scene MouseHandler is referencing removed nodes Changes: https://git.openjdk.java.net/jfx/pull/448/files Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=448&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8264330 Stats: 52 lines in 2 files changed: 51 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jfx/pull/448.diff Fetch: git fetch https://git.openjdk.java.net/jfx pull/448/head:pull/448 PR: https://git.openjdk.java.net/jfx/pull/448
