Revert of Add CHECKs when updating pointers from the slots and store buffers...

Revert of Add CHECKs  when updating pointers from the slots and store buffers (patchset #3 id:40001 of https://codereview.chromium.org/1035763002/)

Reason for revert:
Got one dev-channel with this. Should be enough.

Original issue's description:
> Add CHECKs  when updating pointers from the slots and store buffers
>
> We want to verify that we always overwrite heap objects with heap
> objects, and non-heap objects with non-heap objects
>
> BUG=chromium:452095
> R=hpayer@chromium.org
> LOG=n
>
> Committed: https://crrev.com/58fbcfac8ae82b1241f07e1b8ea81a5973514c11
> Cr-Commit-Position: refs/heads/master@{#27479}

TBR=hpayer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:452095

Review URL: https://codereview.chromium.org/1052713002

Cr-Commit-Position: refs/heads/master@{#27565}

src/heap/heap-inl.h

@@ -547,8 +547,6 @@ void Heap::ScavengeObject(HeapObject** p, HeapObject* object) {
   if (first_word.IsForwardingAddress()) {
     HeapObject* dest = first_word.ToForwardingAddress();
     DCHECK(object->GetIsolate()->heap()->InFromSpace(*p));
-    // TODO(jochen): Remove again after fixing http://crbug.com/452095
-    CHECK((*p)->IsHeapObject() && dest->IsHeapObject());
     *p = dest;
     return;
   }

src/heap/heap.cc

@@ -2424,8 +2424,6 @@ void Heap::ScavengeObjectSlow(HeapObject** p, HeapObject* object) {
   MapWord first_word = object->map_word();
   SLOW_DCHECK(!first_word.IsForwardingAddress());
   Map* map = first_word.ToMap();
-  // TODO(jochen): Remove again after fixing http://crbug.com/452095
-  CHECK((*p)->IsHeapObject() == object->IsHeapObject());
   map->GetHeap()->DoScavengeObject(map, p, object);
 }
 

src/heap/mark-compact.cc

@@ -2892,8 +2892,6 @@ class PointersUpdatingVisitor : public ObjectVisitor {
     // Avoid unnecessary changes that might unnecessary flush the instruction
     // cache.
     if (target != old_target) {
-      // TODO(jochen): Remove again after fixing http://crbug.com/452095
-      CHECK(target->IsHeapObject() == old_target->IsHeapObject());
       rinfo->set_target_object(target);
     }
   }
@@ -2904,8 +2902,6 @@ class PointersUpdatingVisitor : public ObjectVisitor {
     Object* old_target = target;
     VisitPointer(&target);
     if (target != old_target) {
-      // TODO(jochen): Remove again after fixing http://crbug.com/452095
-      CHECK(target->IsHeapObject() == old_target->IsHeapObject());
       rinfo->set_target_address(Code::cast(target)->instruction_start());
     }
   }
@@ -2916,8 +2912,6 @@ class PointersUpdatingVisitor : public ObjectVisitor {
     DCHECK(stub != NULL);
     VisitPointer(&stub);
     if (stub != rinfo->code_age_stub()) {
-      // TODO(jochen): Remove again after fixing http://crbug.com/452095
-      CHECK(stub->IsHeapObject() == rinfo->code_age_stub()->IsHeapObject());
       rinfo->set_code_age_stub(Code::cast(stub));
     }
   }
@@ -2929,9 +2923,6 @@ class PointersUpdatingVisitor : public ObjectVisitor {
             rinfo->IsPatchedDebugBreakSlotSequence()));
     Object* target = Code::GetCodeFromTargetAddress(rinfo->call_address());
     VisitPointer(&target);
-    // TODO(jochen): Remove again after fixing http://crbug.com/452095
-    CHECK(target->IsCode() &&
-          HAS_SMI_TAG(Code::cast(target)->instruction_start()));
     rinfo->set_call_address(Code::cast(target)->instruction_start());
   }
 
@@ -3076,9 +3067,6 @@ static void UpdatePointer(HeapObject** address, HeapObject* object) {
          object->GetHeap()->lo_space()->FindPage(
              reinterpret_cast<Address>(address)) != NULL);
   if (map_word.IsForwardingAddress()) {
-    // TODO(jochen): Remove again after fixing http://crbug.com/452095
-    CHECK((*address)->IsHeapObject() ==
-          map_word.ToForwardingAddress()->IsHeapObject());
     // Update the corresponding slot.
     *address = map_word.ToForwardingAddress();
   }