RFR: JDK-8309884: missing @since tags in `com.sun.source.*` [v2]

[Jonathan Gibbons]

> Please review a trivial docs fix to address missing `@since` tags in `com.sun.source` API.

Jonathan Gibbons has updated the pull request incrementally with one additional commit since the last revision:

  change @since 8 to 1.8

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/14434/files
  - new: https://git.openjdk.org/jdk/pull/14434/files/2ad464c1..f80758b8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14434&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14434&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/14434.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14434/head:pull/14434

PR: https://git.openjdk.org/jdk/pull/14434