RFR: 8284673: Collapse identical catch branches in java.management

[Andrey Turbanov]

Let's take advantage of Java 7 language feature - "Catching Multiple Exception Types".
It simplifies code. Reduces duplication.
Found by IntelliJ IDEA inspection Identical 'catch' branches in 'try' statement

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Commit messages:
 - [PATCH] Collapse identical catch branches in java.management

Changes: https://git.openjdk.java.net/jdk/pull/8161/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8161&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284673
  Stats: 170 lines in 10 files changed: 2 ins; 115 del; 53 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8161.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8161/head:pull/8161

PR: https://git.openjdk.java.net/jdk/pull/8161