message: Don't assert that inactive threads are converging
diff: @@ -1854,7 +1854,7 @@ void Debugger::CalcActiveMask(rdcarray<bool> &activeMask)
  // become uniform again.
  convergeBlock = workgroup[0].mergeBlock;
  for(size_t i = 1; i < workgroup.size(); i++)
  - RDCASSERT(convergeBlock == workgroup[i].mergeBlock);
  + RDCASSERT(!activeMask[i] || convergeBlock == workgroup[i].mergeBlock);
  }
  if(wasDiverged || diverged)
  