[heap] Color object black on unsafe layout change.

src/heap/concurrent-marking-deque.h

Index: src/heap/concurrent-marking-deque.h
diff --git a/src/heap/concurrent-marking-deque.h b/src/heap/concurrent-marking-deque.h
index daa0e2ba4c1ce9129c648eb7ba64881748e30bbb..1490923a2f4a1196d02cec3fb212d49f58c1de25 100644
--- a/src/heap/concurrent-marking-deque.h
+++ b/src/heap/concurrent-marking-deque.h
@@ -47,8 +47,6 @@ class ConcurrentMarkingDeque {
   // deque. The concurrent thread can push to both deques.
   bool Push(HeapObject* object, MarkingThread thread = MarkingThread::kMain,
             TargetDeque target = TargetDeque::kShared) {
-    DCHECK_IMPLIES(thread == MarkingThread::kMain,
-                   target == TargetDeque::kShared);
     switch (target) {
       case TargetDeque::kShared:
         shared_deque_.Push(object);