8075242: Remove SpecializationStats

[Stefan Karlsson]

Hi,

I propose that we remove the SpecializationStats from the 
oop_oop_iterate infrastructure.

This will make it easier for a future conversion of the oop_oop_iterate 
macros into template functions.

Some indications that this feature isn't used that much, is that it 
doesn't compile when turned on and the code in InstanceMirrorKlass and 
InstanceClassLoaderKlass both records that the calls are coming from 
InstanceRefKlass.

Also, the non-inlined, virtual do_oop() calls will show up in a 
profiler, if they have a significant affect on the performance.

http://cr.openjdk.java.net/~stefank/8075242
https://bugs.openjdk.java.net/browse/JDK-8075242

Thanks,
StefanK