RFR: 8259074: regex benchmarks and tests [v5]

[Martin Buchholz]

> 8259074: regex benchmarks and tests

Martin Buchholz has updated the pull request incrementally with one additional commit since the last revision:

  fix imports

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1940/files
  - new: https://git.openjdk.java.net/jdk/pull/1940/files/89638833..2f688a41

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1940&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1940&range=03-04

  Stats: 8 lines in 1 file changed: 0 ins; 7 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1940.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1940/head:pull/1940

PR: https://git.openjdk.java.net/jdk/pull/1940