RFR: 8309515: Stale cached data from Matcher.namedGroups() after Matcher.usePattern() [v3]

[Raffaello Giulietti]

> The cached `namedGroup` field must be invalidated during an invocation of `Matcher.usePattern()`

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

  Added descriptions to the RuntimeExceptions in the test.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/14350/files
  - new: https://git.openjdk.org/jdk/pull/14350/files/dbe40b98..b505b42f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14350&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14350&range=01-02

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/14350.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14350/head:pull/14350

PR: https://git.openjdk.org/jdk/pull/14350