RFR: 8278434: timeouts in test java/time/test/java/time/format/TestZoneTextPrinterParser.java [v2]

[Naoto Sato]

> The proposed fix is to address the performance degradation caused by the fix to JDK-8275721. Some amount of the degradation cannot be avoided as the lookup now falls back up to the bundles at Locale.ROOT. However, by lowering the fallback priority of `regionFormatFallback` than `COMPAT`'s lookup, it can avoid the excess bundle lookups for regions.
> I also changed the test case `TestZoneTextPrinterParser.java`, which currently iterates over 3 nested loops, i.e., all-locales x all-timezones x 8, which is absolutely unnecessary. Made it to sample some locales.
> In addition, I added a microbenchmark for the DateFormatSymbols.getZoneStrings() method. Here is the result:
> 
> Before the fix to JDK-8275721:
> 
> Benchmark                    Mode  Cnt  Score   Error  Units
> ZoneStrings.testZoneStrings    ss    5  6.865 ± 0.696   s/op
> 
> Before the proposed fix:
> 
> Benchmark                    Mode  Cnt   Score   Error  Units
> ZoneStrings.testZoneStrings    ss    5  15.741 ± 4.300   s/op
> 
> After the proposed fix:
> 
> Benchmark                    Mode  Cnt  Score   Error  Units
> ZoneStrings.testZoneStrings    ss    5  9.756 ± 3.685   s/op

Naoto Sato 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 four additional commits since the last revision:

 - Merge branch 'master' into JDK-8278434
 - Copyright year update
 - Added a microbenchmark for zone strings
 - 8278434: timeouts in test java/time/test/java/time/format/TestZoneTextPrinterParser.java

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6790/files
  - new: https://git.openjdk.java.net/jdk/pull/6790/files/f14f5450..5f38bd13

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6790&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6790&range=00-01

  Stats: 20434 lines in 643 files changed: 14380 ins; 3767 del; 2287 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6790.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6790/head:pull/6790

PR: https://git.openjdk.java.net/jdk/pull/6790