[heap] Only visit strong links during scavenge of promoted objects

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 21b0e4c62fa55f82cfcf28a8134c7fb8257f64c0..4be6946c128078f0b09e07ba7730db2d07aceb97 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -473,8 +473,9 @@ class MarkCompactCollector {
   }
 
   INLINE(static bool IsOnEvacuationCandidate(Object* obj)) {
-    return Page::FromAddress(reinterpret_cast<Address>(obj))
-        ->IsEvacuationCandidate();
+    return obj->IsHeapObject() &&
+           Page::FromAddress(reinterpret_cast<Address>(obj))
+               ->IsEvacuationCandidate();
   }
 
   void RecordRelocSlot(Code* host, RelocInfo* rinfo, Object* target);