RFR: 8177819: DateTimeFormatterBuilder zone parsing should recognise DST [v3]

[Naoto Sato]

> This fix intends to honor the type (std/dst/generic) of parsed zone name for selecting the offset at the overlap. Corresponding CSR has also been drafted.

Naoto Sato has updated the pull request incrementally with two additional commits since the last revision:

 - Replaced integer literals.
 - Refined wording #2

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6527/files
  - new: https://git.openjdk.java.net/jdk/pull/6527/files/99ad3cad..89c894ae

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6527&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6527&range=01-02

  Stats: 18 lines in 4 files changed: 2 ins; 1 del; 15 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6527.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6527/head:pull/6527

PR: https://git.openjdk.java.net/jdk/pull/6527