RFR: 8279946: (ch) java.nio.channels.FileChannel tryLock and write methods are missing @throws NonWritableChannelException

[Brian Burkhalter]

Please consider this change which would add `@throws` clauses for `NonWritableChannelException` to the various `tryLock()` and `write()` methods in `java.nio.channels.FileChannel`.

-------------

Commit messages:
 - 8279946: (ch) java.nio.channels.FileChannel tryLock and write methods are missing @throws NonWritableChannelException

Changes: https://git.openjdk.java.net/jdk/pull/7058/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7058&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8279946
  Stats: 23 lines in 1 file changed: 19 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7058.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7058/head:pull/7058

PR: https://git.openjdk.java.net/jdk/pull/7058