[GC] Reverted r39215, which caused the GC to allocate more pools unnecessarily and caused long programs to run out of memory.  This needs some rethinking.
[GC] Reverted r39215, which caused the GC to allocate more pools unnecessarily
and caused long programs to run out of memory.  This needs some rethinking.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@39531 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot