Fix wrong DCHECK in Heap::FindAllocationMemento where bump pointer overflow points to the currently…

src/heap/heap-inl.h

Index: src/heap/heap-inl.h
diff --git a/src/heap/heap-inl.h b/src/heap/heap-inl.h
index b170e04798eaf4bba8d86db01e723337b02f1cb1..fdb1d7345b4d79c0e738f39ab879667f4e604048 100644
--- a/src/heap/heap-inl.h
+++ b/src/heap/heap-inl.h
@@ -452,7 +452,7 @@ AllocationMemento* Heap::FindAllocationMemento(HeapObject* object) {
   Address top = NewSpaceTop();
   DCHECK(memento_address == top ||
          memento_address + HeapObject::kHeaderSize <= top ||
-         !NewSpacePage::OnSamePage(memento_address, top));
+         !NewSpacePage::OnSamePage(memento_address, top - 1));
   if (memento_address == top) return NULL;
 
   AllocationMemento* memento = AllocationMemento::cast(candidate);