RFR: JDK-8234682: The order of @param in the generated docs should match the method signature [v2]

[Hannes Wallnöfer]

> Please review a change in how documentation from `@param` tags is generated. 
> 
> The old code generates parameter documentation for each `@param` in the order in which the tags occur in the comment, then adds documentation from inherited `@param` tags for undocumented parameters. 
> 
> The new code always generates documentation in the order in which actual parameters are declared in the code, using local or inherited `@param` tags as appropriate. Any `@param` tags that do not have a matching parameter are added afterwards.
> 
> Note that `@param` is not just used for parameters of executable members but also type parameters and record components. The second commit of this PR fixes a `ClassCastException` for these uses that was caused by the first commit and adds a few tests for it.

Hannes Wallnöfer has updated the pull request incrementally with one additional commit since the last revision:

  JDK-8234682: Review feedback

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7046/files
  - new: https://git.openjdk.java.net/jdk/pull/7046/files/231ca4d6..1caa8aed

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7046&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7046&range=00-01

  Stats: 5 lines in 2 files changed: 2 ins; 1 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7046.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7046/head:pull/7046

PR: https://git.openjdk.java.net/jdk/pull/7046