This change adds a conditional `search-tags.html` page to list all search tags
defined by the `{@index ... }` tag. Since search tags work very similar to the
`{@systemProperty ...}` tag and are internally represented by the same class I
changed `SystemPropertiesWriter.java` into an abstract base class called
`IndexItemListWriter.java`, with concrete subclasses for system properties and
search tags.
JavaDoc also generates index items for documentation headings, these are not
included in `search-tags.html`.
[This is the Search Tags page for JDK API
docs](https://cr.openjdk.org/~hannesw/8340565/api.00/search-tags.html)
(top-level files only).
-------------
Commit messages:
- Remove trailing whitespace
- Fix comment
- JDK-8340565: Create separate index page for terms defined by the index tag
Changes: https://git.openjdk.org/jdk/pull/21429/files
Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21429&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8340565
Stats: 531 lines in 13 files changed: 363 ins; 161 del; 7 mod
Patch: https://git.openjdk.org/jdk/pull/21429.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/21429/head:pull/21429
PR: https://git.openjdk.org/jdk/pull/21429
