RFR: 8327640: Allow NumberFormat strict parsing [v8]

[Justin Lu]

> Please review this PR and associated [CSR](https://bugs.openjdk.org/browse/JDK-8327703) which introduces strict parsing for NumberFormat.
> 
> The concrete subclasses that will utilize this leniency value are `DecimalFormat` and `CompactNumberFormat`. Strict leniency allows for parsing to be used as an input validation technique for localized formatted numbers. The default leniency mode will remain lenient, and can only be set to strict through an intentional `setLenient(boolean)` method call. Leniency operates differently based off the values returned by `isGroupingUsed()`, `getGroupingSize()`, and `isParseIntegerOnly()`.
> 
> Below is an example of the change, the CSR can be viewed for further detail.
> 
> 
> DecimalFormat fmt = (DecimalFormat) NumberFormat.getNumberInstance(Locale.US);
> fmt.parse("1,,,0,,,00,.23Zabced45");  // returns 1000.23
> fmt.setLenient(false);
> fmt.parse("1,,,0,,,00,.23Zabced45"); // Now throws a ParseException
> fmt.setGroupingSize(2);
> fmt.parse("12,34,567"); // throws ParseException
> fmt.setParseIntegerOnly(true)
> fmt.parse("12,34.56"); // throws ParseException
> fmt.parse("12,34"); // successfully returns the Number 1234
> 
> 
> The associated tests are all localized, and the data is converted properly during runtime.

Justin Lu 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 18 additional commits since the last revision:

 - correct assert statement
 - Merge branch 'master' into JDK-8327640-NumberFormat-strictParsing
 - Reflect test suggestions
 - reflect impl suggestions
 - Merge branch 'master' into JDK-8327640-NumberFormat-strictParsing
 - improve wording consistency and see tags
 - Merge branch 'master' into JDK-8327640-NumberFormat-strictParsing
 - revert cleanup changes; (to go into a separate change)
 - use directed 'inheritDoc' tag
 - update example for lenient parsing
 - ... and 8 more: https://git.openjdk.org/jdk/compare/ada2bc7c...6c9c4692

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18339/files
  - new: https://git.openjdk.org/jdk/pull/18339/files/eec992e3..6c9c4692

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18339&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18339&range=06-07

  Stats: 4628 lines in 184 files changed: 1334 ins; 1373 del; 1921 mod
  Patch: https://git.openjdk.org/jdk/pull/18339.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18339/head:pull/18339

PR: https://git.openjdk.org/jdk/pull/18339