Change DCHECK to CHECK in LayoutListItem::UpdateListMarkerNumbers

Speculative bug fix.

BUG=713671
R=kojii@chromium.org

Review-Url: https://codereview.chromium.org/2840613006
Cr-Commit-Position: refs/heads/master@{#467246}

third_party/WebKit/Source/core/layout/LayoutListItem.cpp

@@ -523,7 +523,7 @@ void LayoutListItem::UpdateListMarkerNumbers() {
     return;
 
   Node* list_node = EnclosingList(this);
-  DCHECK(list_node);
+  CHECK(list_node);
 
   bool is_list_reversed = false;
   HTMLOListElement* o_list_element =