RFR: 8223607: --override-methods=summary ignores some signature changes

[Hannes Wallnöfer]

This change causes overriding methods to be documented in the details section under some conditions even when javadoc is run with `--override-methods=summary` and the method does not have a doc comment. Previously this already happened when the overriding method had a covariant return type (JDK-8219147). The following conditions will now trigger the same behaviour:

 - method visibility changes from `protected` to `public`
 - any change in thrown exceptions
 - change in documented annotations anywhere in the method signature

The conditions are simple by intention as we don't want to do checks that add to much complexity (such as distinguishing between checked and unchecked exceptions) and instead want to set the bar for inclusion in the details section relatively low.

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Commit messages:
 - JDK-8223607: --overridden-methods=summary ignores some signature changes

Changes: https://git.openjdk.java.net/jdk/pull/1734/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1734&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8223607
  Stats: 415 lines in 6 files changed: 393 ins; 13 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1734.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1734/head:pull/1734

PR: https://git.openjdk.java.net/jdk/pull/1734