RFR: 8349750: [TestBug] NodeInitializationStressTest: remaining Nodes [v2]

[Andy Goryachev]

> ## Added Missing Controls
> 
> ButtonBar
> ProgressIndicator
> Separator
> Slider,
> 
> ## Added Node Classes
> 
> AnchorPane
> AmbientLight
> Arc
> BorderPane
> Box
> Circle
> CubicCurve
> Cylinder
> DialogPane
> DirectionalLight
> Ellipse
> FlowPane
> GridPane
> Group
> HBox
> ImageView
> Line
> MediaView
> MeshView
> Pane
> ParallelCamera
> Path
> PerspectiveCamera
> PointLight
> Polygon
> Polyline
> QuadCurve
> Rectangle
> Region
> Sphere
> StackPane
> SVGPath
> TilePane
> VBox
> 
> 
> ## Miscellaneous
> 
> - minor improvements
> - remove tests that execute show() in non-fx threads per [JDK-8350048](https://bugs.openjdk.org/browse/JDK-8350048)
> 
> 
> 
> ## Not Included Due to Threading Limitations
> 
> HTMLEditor
> MenuBar
> SwingNode
> WebView
> 
> ## Note to the Reviewers
> 
> To avoid merge conflicts, the preferred order of integrations:
> 
> #1697 
> #1713 
> #1717

Andy Goryachev has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 14 commits:

 - review comments
 - Merge remote-tracking branch 'origin/master' into 8349750.stress.2
 - cleanup
 - images
 - Merge remote-tracking branch 'origin/master' into 8349750.stress.2
 - media
 - Merge remote-tracking branch 'origin/master' into 8349750.stress.2
 - 3d
 - shapes
 - show()
 - ... and 4 more: https://git.openjdk.org/jfx/compare/f38ab33b...a8b892ab

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

Changes: https://git.openjdk.org/jfx/pull/1713/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1713&range=01
  Stats: 867 lines in 2 files changed: 828 ins; 13 del; 26 mod
  Patch: https://git.openjdk.org/jfx/pull/1713.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1713/head:pull/1713

PR: https://git.openjdk.org/jfx/pull/1713