[jdk16] RFR: JDK-8247994: Localize javadoc search [v2]

[Jonathan Gibbons]

> This is for JDK16, as a precursor to fixing JDK-8258002.
> 
> While it is good to be using localized strings in the generated output, the significance for JDK-8258002 is that the strings are now obtained from a resource file, and not hardcoded in JavaScript file itself.
> 
> The source file `search.js` is renamed to `search.js.template`, and (unlike other template files) is copied as-is into the generated image. The values in the template are resolved when javadoc is executed, depending on the locale in use at the time. Because of the change in the file's extension, two makefiles are updated to accommodate the new extension: one is for the "interim" javadoc used to generate the API docs; the other is for the primary javadoc in the main JDK image.

Jonathan Gibbons has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge remote-tracking branch 'upstream/master' into localize.search.js
 - JDK-8247994: Localize javadoc search

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

Changes:
  - all: https://git.openjdk.java.net/jdk16/pull/16/files
  - new: https://git.openjdk.java.net/jdk16/pull/16/files/8eb7f27b..ec111185

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk16&pr=16&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk16&pr=16&range=00-01

  Stats: 1532 lines in 52 files changed: 1207 ins; 121 del; 204 mod
  Patch: https://git.openjdk.java.net/jdk16/pull/16.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16 pull/16/head:pull/16

PR: https://git.openjdk.java.net/jdk16/pull/16