RFR: 8261221: Tooltip bigger than screen size blinks - shows and hides over and over again [v4]

[Paweł Kruszczyński]

> `Tooltip` is no longer hiding upon receiving `MouseEvent.MOUSE_ENTERED_TARGET` event inside it. Pressing mouse on overlaying tooltip also kills the tooltip, so the infinite duration tooltip can be closed.

Paweł Kruszczyński has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:

 - Merge branch 'openjdk:master' into 8261221_tooltip_blinks
 - Merge branch 'openjdk:master' into 8261221_tooltip_blinks
 - 8261221: Tooltip bigger than screen size blinks - applying reviewed fixes
 - 8261221: Tooltip bigger than screen size blinks - shows and hides over and over again

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

Changes:
  - all: https://git.openjdk.java.net/jfx/pull/395/files
  - new: https://git.openjdk.java.net/jfx/pull/395/files/0a175dca..7dc2ff37

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=395&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=395&range=02-03

  Stats: 5600 lines in 7 files changed: 5583 ins; 3 del; 14 mod
  Patch: https://git.openjdk.java.net/jfx/pull/395.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/395/head:pull/395

PR: https://git.openjdk.java.net/jfx/pull/395