[Preliminary] RFR JDK-8064925: URLConnection::getContent needs to be updated to work with modules

[Pavel Rappo]

Hi everyone,

Could you please review my change for JDK-8064925?

http://cr.openjdk.java.net/~prappo/8064925/webrev.01/

The main goal is to see if the proposed spec change and the overall approach are
correct.

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So what has happened in this change?

1. java.net.URLConnection.getContentHandler method now looks for
ContentHandlerFactories also via ServiceLoader mechanism.

2. Existing image & audio handlers in java.desktop has been moved from
'sun.net.www.content' package to 'sun.awt.www.content'; A ContentHandlerFactory
called 'sun.awt.www.content.MultimediaContentHandlers' has been introduced to
help ServiceLoader to discover these handlers. 

P.S. All names described in (2) are subject to agreement with awt-dev at openjdk.java.net

-Pavel