8034043/8034026 - clean up of a few native code issues to align things with modules

[Alan Bateman]

This patch is a clean-up to fix a number issues that arise trying to 
align native libraries with possible future modules.

The first is the preferences API where the native code is currently 
linked into libjava for Windows/Linux/Solaris and libosx on OS X. This 
patch moves the native sources down to a prefs sub-directory (to follow 
long standing conventions) and links the resulting code into a new 
libprefs (all platforms). The rational for this is that the preferences 
API is a reasonable candidate for a module and it is odd to have its 
native methods in libraries that are likely to be in other modules. See 
also JDK-8034074 [1] for an opportunity for anyone so inclined to 
eliminate some of this code.

The logging API is another case where it has native code linked into 
libjava. It's for the somewhat obscure case where the VM is running as a 
setuid process and the FileHandler is configured to include the user's 
home directory. For now, I've moved this to sun.misc.VM on the 
assumption that there may be other places where we need to know if we 
are running with setuid. We have to do a general clean-up of sun.misc 
and that may be the time to move it to a better home.

In the security area then the OS X implementation of the native methods 
for sun.security.krb5.SCDynamicStoreConfig were put in the wrong 
location by the OS X port (src/macosx/native/java/util???) and also 
linked to the wrong library (libosx.dylib). This patch moves the source 
and links it into existing libosxkrb5.dylib along with the other OS X 
specific Kerberos code. This is code that is not exercised by the tests 
as it requires Open Directory to be configured. Thanks to Max Wang for 
trying out a preliminary version of this patch to ensure that it 
continues to work.

One comment on SecurityLibraries.gmk is it's using hardcoded paths to 
the OS X frameworks. Erik Joelsson told me that this is on the build 
group's list of things to fix up in the future.

The webrev with the proposed changes is here:

http://cr.openjdk.java.net/~alanb/8034043%2b8034026/webrev/

-Alan.

[1] https://bugs.openjdk.java.net/browse/JDK-8034074