RFR: 8207759: VK_ENTER not consumed by TextField when default Button exists

[Jeanette Winzenburg]

This is a fix for https://bugs.openjdk.java.net/browse/JDK-8207759

The issue is that default/cancel button on a scene are triggered even though a onKeyPressed handler for ENTER/CANCEL consumes the keyEvent. See the bug for details on both cause and fix.

There are additional/changed tests to verify the fix. All old tests are passing.

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Commits:
 - 93556393: Fix: VK_ENTER not consumed by TextField when default Button exists

Changes: https://git.openjdk.java.net/jfx/pull/15/files
 Webrev: https://webrevs.openjdk.java.net/jfx/15/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8207759
  Stats: 553 lines in 8 files changed: 528 ins; 20 del; 5 mod
  Patch: https://git.openjdk.java.net/jfx/pull/15.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/15/head:pull/15

PR: https://git.openjdk.java.net/jfx/pull/15