RFR: 8232811: Dialog's preferred size no longer accommodates multi-line strings

[Thiago Milczarek Sayao]

https://bugs.openjdk.java.net/browse/JDK-8232811

This one was hard to tackle.

./gradlew -PFULL_TEST=true -PUSE_ROBOT=true :systemTests:test --tests test.robot.javafx.scene.dialog.DialogWithOwnerSizingTest

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Commits:
 - 338bedbe: Fix mistake
 - a02894d6: Fix JDK-8232811
 - 7a23cdbd: Merge pull request #2 from openjdk/master
 - fc36a292: Merge pull request #1 from openjdk/master

Changes: https://git.openjdk.java.net/jfx/pull/63/files
 Webrev: https://webrevs.openjdk.java.net/jfx/63/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8232811
  Stats: 188 lines in 2 files changed: 176 ins; 11 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/63.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/63/head:pull/63

PR: https://git.openjdk.java.net/jfx/pull/63