RFR: JDK-8293776 : Adds CSS 4 and 8 digits hex coded Color [v6]

[ScientificWare]

> This is referenced in Java Bug Database as
> - [JDK-8293776 : Adds CSS 4 and 8 digits hex coded Color](https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8293776)
> 
> This is tracked in JBS as 
> - [JDK-8293776 : Adds CSS 4 and 8 digits hex coded Color](https://bugs.openjdk.java.net/browse/JDK-8293776)
> 
> Adds the 4 and 8 digits color hex notations to CSS.java, as described in :
> CSS Color Module Level 4
> W3C Candidate Recommendation Snapshot, 5 July 2022
> [6.2 The RGB Hexadecimal Notations: `#RRGGBB`](https://www.w3.org/TR/css-color-4/#hex-notation)
> 
> Designed from : [ScientificWare JDK-8293776 : Adds CSS 4 and 8 digits hex coded Color](https://github.com/scientificware/jdk/issues/13)

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

  Corrects typos and digit extraction.
  
  Corrects typos.
  And applies a better digit extraction as suggested in main-line review thread.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/10317/files
  - new: https://git.openjdk.org/jdk/pull/10317/files/59709803..e6454c11

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10317&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10317&range=04-05

  Stats: 14 lines in 1 file changed: 0 ins; 0 del; 14 mod
  Patch: https://git.openjdk.org/jdk/pull/10317.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10317/head:pull/10317

PR: https://git.openjdk.org/jdk/pull/10317