RFR: 8253089: Windows (MSVC 2017) build fails after JDK-8243208

[Aleksey Shipilev]

It seems that MSVC 2017 is getting confused about the differences in `unsigned int` and `u2`. After a few attempts at
fixing this, I think we need to use `u2` consistently for hash code computations.

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Commit messages:
 - No need to cast to short
 - Indenting
 - Minor cleanup
 - Another try, use u2 consistently
 - 8253089: Windows (MSVC 2017) build fails after JDK-8243208

Changes: https://git.openjdk.java.net/jdk/pull/150/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=150&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8253089
  Stats: 8 lines in 2 files changed: 0 ins; 0 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk/pull/150.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/150/head:pull/150

PR: https://git.openjdk.java.net/jdk/pull/150