Happy path

[Roland Westrelin]

Here is a new webrev:

http://cr.openjdk.java.net/~roland/shenandoah/happypath-nocoalescing/webrev.00/

I hit a failure:

#  Internal Error (/home/roland/shenandoah/src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp:104), pid=10983, tid=11560          
#  Error: Shenandoah assert_forwarded failed; Object should be forwarded     

once with this. I couldn't reproduce it.

Roland.