RFR: 8092102: Labeled: truncated property [v3]

[Andy Goryachev]

> Adds **Labeled.textTruncated** property which indicates when the text is visually truncated (and the ellipsis string is inserted) in order to fit the available width.
> 
> The new property reacts to changes in the following properties:
> - ellipsisString
> - font
> - height
> - text
> - width
> - wrapText
> 
> I don't think it's worth creating a headful test (headless won't work) due to relative simplicity of the code.
> 
> **Alternative**
> 
> The desired functionality can be just as easily achieved on an application level, by adding a similar property to a subclass.  What is the benefit of adding this functionality to the core?
> 
> **See Also**
> 
> * [JDK-8091891](https://bugs.openjdk.org/browse/JDK-8091891) TreeView: There is no tooltip available on truncated node
> * [JDK-8205211](https://bugs.openjdk.org/browse/JDK-8205211) Ability to show Tooltip only when text is shown with ellipsis (...)

Andy Goryachev 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 five additional commits since the last revision:

 - handle tree/table view cells
 - Merge remote-tracking branch 'origin/master' into 8092102.truncated
 - review comments
 - Merge remote-tracking branch 'origin/master' into 8092102.truncated
 - 8092102 Labeled: truncated property

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/1389/files
  - new: https://git.openjdk.org/jfx/pull/1389/files/8a5cb17e..72f170b6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1389&range=02
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1389&range=01-02

  Stats: 85 lines in 5 files changed: 72 ins; 4 del; 9 mod
  Patch: https://git.openjdk.org/jfx/pull/1389.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1389/head:pull/1389

PR: https://git.openjdk.org/jfx/pull/1389