RFR: 8366017: Extend the set of inputs handled by fast paths in FloatingDecimal [v4]

[Raffaello Giulietti]

> Yet another step in modernizing `FloatingDecimal`s floating-point parsing.

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

  Added tests to exercise fast paths.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/26990/files
  - new: https://git.openjdk.org/jdk/pull/26990/files/7c5cd927..21118e9d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26990&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26990&range=02-03

  Stats: 82 lines in 2 files changed: 80 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26990.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26990/head:pull/26990

PR: https://git.openjdk.org/jdk/pull/26990