RFR [15] 8238167: Remove stray files from jdk.javadoc

[Pavel Rappo]

Hello,

Please review the change for https://bugs.openjdk.java.net/browse/JDK-8238167:

  http://cr.openjdk.java.net/~prappo/8238167/webrev.00/

This is a cleanup change that removes a couple of files that I have not found
to be of any use.

The first file, jquery.js, was introduced in

    changeset:   33920:bd731341c405
    user:        bpatel
    date:        Fri Nov 20 20:55:07 2015 +0000
    summary:     8141492: Implement search feature in javadoc

That same changeset also brought the jquery-1.10.2.js file. While the contents
of these files were identical, only the latter file was used. Since then both
files have been updated together, with the same content. Every time that happened,
the latter file, jquery-1.10.2.js, was simultaneously renamed to reflect the
version of the JQuery library it was updated with.
As of today, jquery.js is still not used.

The second file, help.html, is part of the test scenario. The file first appeared in

    changeset:   36705:890c250d8da8
    parent:      36503:4a95f4b1bd8b
    user:        ksrini
    date:        Mon Mar 14 15:04:57 2016 -0700
    summary:     8071982: Update tests for revamped Doclet API

I flagged this file as suspicious while testing the change for 8237909: Remove
zipped index files feature. I noticed that the TestOptions test did not seem to
care whether the JSZip library was present or not, despite the fact that its
resource, help.html, explicitly referred to that library. Further investigation
showed that this file was never used by that test, or anyone for that matter.
The javadoc tool has only a handful of "help" options:

    javadoc -help | grep help
        --help, -help, -?, -h
        --help-extra, -X
        -helpfile <file>
                      Include file that help link links to
        -nohelp       Do not generate help link

all of which are covered by the TestHelpOption and TestXOption tests. There
doesn't seem to be any need in testing anything related to "help" options in
TestOptions. Its @summary, otherwise very specific, certainly doesn't mention
anything like that.

    ***

Both files, jquery.js and help.html, have been diligently updated over the
years. They seem to be leftovers from the development stage. Since they are not
used, updating those files is a burden to maintainers and provides nothing in
return. I propose to delete them.

All javadoc tests pass, and the functionality of the generated pages
seems to be intact.

Thanks,
-Pavel