RFR: 8295823: Use enhanced-for cycle instead of Enumeration in java.naming

[Andrey Turbanov]

`java.util.Enumeration` is a legacy interface from java 1.0.
There are couple of cycles which use it to iterate over collections. We can replace this manual cycle with enchanced-for, which is shorter and easier to read.

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Commit messages:
 - [PATCH] Use enhanced-for cycle instead of Enumeration in java.naming

Changes: https://git.openjdk.org/jdk/pull/10804/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10804&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295823
  Stats: 5 lines in 2 files changed: 0 ins; 1 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/10804.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10804/head:pull/10804

PR: https://git.openjdk.org/jdk/pull/10804