RFR: 8279283 - BufferedInputStream should override transferTo [v6]

[Markus KARG]

> Implementation of JDK-8279283

Markus KARG has updated the pull request incrementally with one additional commit since the last revision:

  using getBufIfOpen() instead of direct buf access

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Changes:
  - all: https://git.openjdk.org/jdk/pull/6935/files
  - new: https://git.openjdk.org/jdk/pull/6935/files/0d3528ea..2c415d0c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=6935&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=6935&range=04-05

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/6935.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/6935/head:pull/6935

PR: https://git.openjdk.org/jdk/pull/6935