RFR: 8341670: [Text, TextFlow] Public API for Text Layout Info [v29]

[Andy Goryachev]

> Please refer to
> 
> https://github.com/andy-goryachev-oracle/Test/blob/main/doc/Text/LayoutInfo.md
> 
> The RichTextArea control ([JDK-8301121](https://bugs.openjdk.org/browse/JDK-8301121)), or any custom control that needs non-trivial navigation within complex or wrapped text needs a public API to get information about text layout.
> 
> This change fixes the missing functionality by adding a new public method to the `Text` and `TextFlow` classes.:
> 
> 
>     /**
>      * Obtains the snapshot of the current text layout information.
>      * @return the layout information
>      * @since 25
>      */
>     public final LayoutInfo getLayoutInfo()
> 
> 
> The `LayoutInfo` provides a view into the text layout within `Text`/`TextFlow` nodes such as:
> 
> - caret information
> - text lines: offsets and bounds
> - overall layout bounds
> - text selection geometry
> - strike-through geometry
> - underline geometry
> 
> 
> 
> 
> ## WARNING
> 
> Presently, information obtained via certain Text/TextField methods is incorrect with non-zero padding and borders, see [JDK-8341438](https://bugs.openjdk.org/browse/JDK-8341438).
> 
> This PR provides correct answers in the new API, leaving the behavior of the existing methods unchanged (there is a compatibility risk associated with trying to fix [JDK-8341438](https://bugs.openjdk.org/browse/JDK-8341438) ).
> 
> 
> 
> ## Testing
> 
> The new APIs can be visually tested using the Monkey Tester on this branch:
> https://github.com/andy-goryachev-oracle/MonkeyTest/tree/text.layout.api
> 
> in the Text and TextFlow pages:
> ![Screenshot 2024-11-04 at 11 38 21](https://github.com/user-attachments/assets/2e17e55c-f819-4742-8a42-b9af2b6bac72)
> 
> Two very basic headful tests have been added.
> 
> 
> ## See Also
> 
> https://github.com/FXMisc/RichTextFX/pull/1246

Andy Goryachev has updated the pull request incrementally with one additional commit since the last revision:

  removed getStrikeThroughShape

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/1596/files
  - new: https://git.openjdk.org/jfx/pull/1596/files/c885173b..0f02fe9d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1596&range=28
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1596&range=27-28

  Stats: 8 lines in 2 files changed: 2 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jfx/pull/1596.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1596/head:pull/1596

PR: https://git.openjdk.org/jfx/pull/1596