RFR: 8274395: Use enhanced-for instead of plain 'for' in jdk.internal.jvmstat [v2]

[Andrey Turbanov]

> There are few places in code where manual `for` loop is used with Iterator to iterate over Collection or Array.
> Instead of manual `for` cycles it's preferred to use enhanced-for cycle instead: it's less verbose, makes code easier to read and it's less error-prone.
> It doesn't have any performance impact: javac compiler generates similar code when compiling enhanced-for cycle.
> Similar cleanups:
> 1. [JDK-8274016](https://bugs.openjdk.java.net/browse/JDK-8274016) java.desktop
> 2. [JDK-8274237](https://bugs.openjdk.java.net/browse/JDK-8274237) java.base
> 3. [JDK-8274261](https://bugs.openjdk.java.net/browse/JDK-8274261) jdk.jcmd
> 4. [JDK-8274318](https://bugs.openjdk.java.net/browse/JDK-8274318) java.management

Andrey Turbanov has updated the pull request incrementally with one additional commit since the last revision:

  8274395: Use enhanced-for instead of plain 'for' in jdk.internal.jvmstat
  update copyright

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/5580/files
  - new: https://git.openjdk.java.net/jdk/pull/5580/files/7967fb43..5ecf5960

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=5580&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=5580&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5580.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5580/head:pull/5580

PR: https://git.openjdk.java.net/jdk/pull/5580