Review request (L) 8003419: NPG: Clean up metadata created during class loading if failure

[Coleen Phillimore]

Summary: Store metadata on ClassFileParser instance to be cleaned up by 
destructor.  This enabled some refactoring of the enormous 
parseClassFile function.

Note: I moved out code that lays out the java object into it's own 
function, but the diffs made it look like I made more than minor 
changes.  The changes I made was changing class_name to _class_name and 
cp to _cp, and not more than that.   To see these changes, you'll have 
to look at before/after code and not the diffs.  I also tried moving 
this layout_fields() function around to it wouldn't false match but I 
wanted to keep it next to parseClassFile() and not move it too far away.

Tested with runThese jck, jck8 lang and vm, NSK vm.quick.testlist, 
java/lang/invoke jtreg tests and java/lang/instrument jtreg tests.

open webrev at http://cr.openjdk.java.net/~coleenp/8003419/
bug link at http://bugs.sun.com/view_bug.do?bug_id=8003419

Thanks,
Coleen