[11u] RFR (S) 8212673: jtreg/applications/runthese/RunThese30M.java fails in C2 with "assert(!had_error) failed: bad dominance"

[Aleksey Shipilev]

Original bug:
  https://bugs.openjdk.java.net/browse/JDK-8212673
  https://hg.openjdk.java.net/jdk/jdk/rev/bac05440d98c

Note it includes the reversal of:
  https://bugs.openjdk.java.net/browse/JDK-8212603
  https://hg.openjdk.java.net/jdk/jdk/rev/6eb876ac6827

...and therefore does not apply cleanly to 11u. I would prefer we push this single change, without
prior (obviously broken) JDK-8212603. I believe Oracle did the same, as they have 11.0.6-oracle only
on this issue.

qfolding both changes yields this 11u webrev:
  https://cr.openjdk.java.net/~shade/8212673/webrev.11u.01/

Testing: Linux x86_64 fastdebug: tier1, tier2

-- 
Thanks,
-Aleksey