<i18n dev> RFR: 8278434: timeouts in test java/time/test/java/time/format/TestZoneTextPrinterParser.java

[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

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Commit messages:
 - Added a microbenchmark for zone strings
 - 8278434: timeouts in test java/time/test/java/time/format/TestZoneTextPrinterParser.java

Changes: https://git.openjdk.java.net/jdk/pull/6790/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6790&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8278434
  Stats: 72 lines in 3 files changed: 59 ins; 7 del; 6 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