CRR (XS): 7113006: G1: excessive ergo output when an evac failure happens

[Tony Printezis]

Hi all,

Can I have a couple of code review for this very small change?

http://cr.openjdk.java.net/~tonyp/7113006/webrev.0/

The excessive ergo output was generated by repeated failed heap 
expansion attempts during a GC. I slightly expanded (pun unintended!) 
the scope of the CR to not only stop generating the ergo output after 
the first failed heap expansion but also to not re-attempt the heap 
expansion. If heap expansion fails once, it will probably fail again so 
it's pointless to keep trying. Without doing a careful and in-depth 
performance analysis I see a mild improvement in GC times when an alloc 
failure happens with this fix.

Tony