RFR: 8301043: Super-interface for PrintStream and PrintWriter [v2]

[Tingjun Yuan]

> Add `java.io.PrintOutput` to represent print operations, and modify `java.io.PrintStream` and `java.io.PrintWriter` to implement it.

Tingjun Yuan has updated the pull request incrementally with one additional commit since the last revision:

  Fix grammar mistakes in the doc

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12277/files
  - new: https://git.openjdk.org/jdk/pull/12277/files/0c8495da..645e30d7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12277&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12277&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/12277.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12277/head:pull/12277

PR: https://git.openjdk.org/jdk/pull/12277