RFR: 8314258: checked_cast doesn't properly check some cases

[Kim Barrett]

Please review this addition of the `integer_cast` utility.

Details in first comment, to avoid email spamming from automatic messages.

Testing: mach5 tier1-5 with `checked_cast` for integral types changed to call
the new `integer_cast`.  Addition of `integer_cast` includes gtests.

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Commit messages:
 - add integer_cast

Changes: https://git.openjdk.org/jdk/pull/29582/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29582&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8314258
  Stats: 378 lines in 2 files changed: 378 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/29582.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29582/head:pull/29582

PR: https://git.openjdk.org/jdk/pull/29582