RFR: JDK-8262421: doclint warnings in jdk.compiler module

[Jonathan Gibbons]

Please review this doc fix to provide a couple of missing `@param` tags

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Commit messages:
 - JDK-8262421: doclint warnings in jdk.compiler module

Changes: https://git.openjdk.java.net/jdk/pull/2731/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2731&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8262421
  Stats: 10 lines in 2 files changed: 6 ins; 1 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2731.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2731/head:pull/2731

PR: https://git.openjdk.java.net/jdk/pull/2731