RFR: 8329537: Nested and enclosing classes should be linked separately in breadcrumb navigation [v2]

[Hannes Wallnöfer]

> Please review a patch to change the breadcrumb sub-navigation in API docs to display nested classes as separate links. 
> 
> The change itself is simple, I replaced the `getBreadCrumbLink` method in `HtmlDocletWriter` which returned a link for a single element with a new `addBreadCrumbLinks` method in `Navigation` which recursively adds all breadcrumb links to a list. Moving the code from `HtmlDocletWriter` to `Navigation` allowed me to remove a lot of code because it is no longer necessary to override the `getNavBar` method in a lot of writer subclasses.
> 
> I compared the JDI API documentation with and without this patch and there were no changes except for the breadcrumb links for nested classes.

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

  Address review feedback, simplify comment

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/19466/files
  - new: https://git.openjdk.org/jdk/pull/19466/files/1468be35..ea959c59

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19466&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19466&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/19466.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19466/head:pull/19466

PR: https://git.openjdk.org/jdk/pull/19466