[heap] Fix IterateBlackObject for fixed arrays in large object space

src/heap/incremental-marking.cc

Index: src/heap/incremental-marking.cc
diff --git a/src/heap/incremental-marking.cc b/src/heap/incremental-marking.cc
index 471f7a6461cdd2ab133633c0dcbf4d3a02d42ab0..26b1c5d58f52353951ae7ff64efbf1bcd8ca9b95 100644
--- a/src/heap/incremental-marking.cc
+++ b/src/heap/incremental-marking.cc
@@ -277,6 +277,11 @@ class IncrementalMarkingMarkingVisitor
 
 void IncrementalMarking::IterateBlackObject(HeapObject* object) {
   if (IsMarking() && Marking::IsBlack(Marking::MarkBitFrom(object))) {
+    Page* page = Page::FromAddress(object->address());
+    if ((page->owner() != nullptr) && (page->owner()->identity() == LO_SPACE)) {
+      // IterateBlackObject requires us to visit the hole object.
+      page->ResetProgressBar();
+    }
     IncrementalMarkingMarkingVisitor::IterateBody(object->map(), object);
   }
 }