[11u] RFR 8239477: jdk/jfr/jcmd/TestJcmdStartStopDefault.java fails -XX:+VerifyOops with "verify_oop: rsi: broken oop"

[Aleksey Shipilev]

Original fix:
  https://bugs.openjdk.java.net/browse/JDK-8239477
  https://hg.openjdk.java.net/jdk/jdk/rev/1dfb43020070

CIs that run testing -XX:+VerifyOops with 11u fail without this.

11u fix is a bit different, because the context is a bit different around this line:
 __ branch(lir_cond_equal, T_OBJECT, L_end->label());

11u webrev:
  http://cr.openjdk.java.net/~shade/8239477/webrev.11u.01/

Testing: affected test (used to fail, now it passes); tier{1,2}; jdk_jfr

-- 
Thanks,
-Aleksey