8177474: Do not emit warnings when illegal access is allowed by --add-exports/--add-opens

[Alan Bateman]

I'd like to get jdk9/dev updated to align with the latest proposal for 
--add-exports/--add-opens to not emit warnings. I've put the webrev with 
the changes here:

     http://cr.openjdk.java.net/~alanb/8177474/webrev/index.html

Some of this is just reverting some of the changes that were in JDK-8174823.

I've expanded the test coverage to cover cases where 
--permit-illegal-access is used with the precise options. These tests 
ensure that there isn't any warnings emitted when access is allowed via 
the precise options.

Once these changes are in jdk9/dev then I will pull them down to jake.

-Alan