RFR: 8372298: RichTextArea: missing API: applyParagraphStyle [v3]

[Andy Goryachev]

> A missing protected method in StyledTextModel prevents from toggling of an individual paragraph attribute.
> 
> This can be tested with he latest Monkey Tester
> https://github.com/andy-goryachev-oracle/MonkeyTest
> 
> - select the RichTextArea page
> - select the RichTextArea model
> - select Control -> Context Menu -> RichTextArea menu
> - type in several paragraphs
> - select all and apply one paragraph attribute, let's say Paragraph Styles -> Background -> (any non-null)
> - select a subset of previously selected paragraphs and apply a second paragraph attribute, let's say Paragraph Styles -> Bullet -> (any non-null)

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 four additional commits since the last revision:

 - Merge branch 'master' into 8372298.apply
 - since
 - test
 - fix

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/1980/files
  - new: https://git.openjdk.org/jfx/pull/1980/files/0a7e6bb9..20fe2077

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1980&range=02
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1980&range=01-02

  Stats: 314 lines in 5 files changed: 202 ins; 45 del; 67 mod
  Patch: https://git.openjdk.org/jfx/pull/1980.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1980/head:pull/1980

PR: https://git.openjdk.org/jfx/pull/1980