8156500: Move Reference pending list into VM to prevent deadlocks
Summary: Move reference pending list and locking into VM
Reviewed-by: coleenp, dholmes, dcubed, mchung, plevart
Contributed-by: kim.barrett@oracle.com, per.liden@oracle.com

8153302: [BACKOUT] STW phases at Concurrent GC should count in PerfCounter
Reviewed-by: jmasa, jwilhelm

8151674: STW phases at Concurrent GC should count in PerfCounter
Reviewed-by: jmasa, sla, tschatzl

8151601: Cleanup locking of the Reference pending list
Reviewed-by: brutisso, stefank

8065331: Add trace events for failed allocations
Reviewed-by: brutisso, ehelin

8134626: Misc cleanups after generation array removal
Reviewed-by: david, dholmes, tschatzl

8077842: Remove the level parameter passed around in GenCollectedHeap
Reviewed-by: kbarrett, mgerdin

8079792: GC directory structure cleanup
Reviewed-by: brutisso, stefank, david