RFR (M) #5 CR 8003985: Support @Contended annotation

[Aleksey Shipilev]

Hi,

This is the final call for reviews for @Contended:
  http://cr.openjdk.java.net/~shade/8003985/webrev.01/

Changes:
 - VM: none since latest revision.
 - JDK: pruned some Javadocs as requested by CCC reviewers

Testing:
 - (respin to make sure everything still intact)
 - Test8003985 passes on Linux x86_64
 - JPRT builds passed
 - JPRT testing passed

Status:
 - This change is ready to be pushed
 - JEP-142 is in Funded state (http://openjdk.java.net/jeps/142)
 - CCC is in place, and Approved

I would need a sponsor to push this.

Thanks,
Aleksey.