RFR: 8276970: Default charset for PrintWriter that wraps PrintStream

[Naoto Sato]

Fixing the default charset for PrintWriter/OutputStreamWriter that wraps a PrintStream to its charset. This issue was raised during the conversations in https://github.com/openjdk/jdk/pull/5771
A corresponding CSR has also been drafted: https://bugs.openjdk.java.net/browse/JDK-8277078

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Commit messages:
 - 8276970: Default charset for PrintWriter that wraps PrintStream

Changes: https://git.openjdk.java.net/jdk/pull/6401/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6401&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8276970
  Stats: 129 lines in 4 files changed: 121 ins; 0 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6401.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6401/head:pull/6401

PR: https://git.openjdk.java.net/jdk/pull/6401