RFR: JDK-8222793 Javadoc tool ignores "-locale" param and uses default locale for all messages and texts

[Jonathan Gibbons]

Please review a medium-small fix for a regression in the new doclet.

The problem is that the -locale option is not being handled correctly, 
and is not taking effect as it should.

[Note: for a while, I was confusing the issue with a related related of 
possibly using different locales for the console messages and the 
generated docs. This is not that one.]

The root cause is that some doclet objects are being initialized either 
too early or in the wrong order. The fix is to address the order of 
initialization, which allowed some unexpected additional cleanup.

The locale option is picked up in the first pass over the options in 
Start, which determines the doclet and locale. After that first pass, 
the doclet is created and its init method called, passing in the locale. 
But, inside the doclet, the configuration object and some of its 
contents were created in the doclet's constructor, before the init 
method is called with the locale to use.  They end up seeing a null 
locale, which translates to the default locale.

The fix is to delay initializing the configuration until the init 
method, which has the downside of making it not final, but the 
unexpected upside is that inside the configuration, a couple of lazy 
init methods can be removed, and the corresponding fields themselves 
made final. (So, net increase in final fields; yay!)

The test is a bit tricky. We need to make sure that setting the -locale 
option correctly affects the various forms of generated output. But by 
default, the only locales we provide are asian and working with those 
Unicode characters can be challenging for some of us.  The solution is 
to generate a new set of resource files with similar-but-different 
content, and to install them in a different "test" locale.  Any easy 
conversion is to convert the values in the property files to upper case, 
and then to use another English locale, such as en_UK.  The easiest way 
to install new resource files is to use the --patch-module VM option, 
which means running javadoc in a child VM, which means we can't use the 
standard JavadocTester framework, which always uses same-vm mode. But, 
it's easy enough to use the toolbox library classes instead. The test 
runs javadoc a few times, with and without the -locale option, and 
verifies the generated text is coming from either the default resource 
bundle, or the uppercased resource bundle, as appropriate.

The changeset has been tested on all standard platforms.

-- Jon

JBS: https://bugs.openjdk.java.net/browse/JDK-8222793
Webrev: http://cr.openjdk.java.net/~jjg/8222793/webrev/