1 files changed, 5 insertions, 1 deletions
diff --git a/dom/base/nsAttrAndChildArray.h b/dom/base/nsAttrAndChildArray.h
index f34370c43..ffbad196c 100644
--- a/dom/base/nsAttrAndChildArray.h
+++ b/dom/base/nsAttrAndChildArray.h
@@ -135,6 +135,9 @@ public:
     return MappedAttrCount();
   }
 
+  // Force this to have mapped attributes, even if those attributes are empty.
+  nsresult ForceMapped(nsMappedAttributeElement* aContent, nsIDocument* aDocument);
+
 private:
   nsAttrAndChildArray(const nsAttrAndChildArray& aOther) = delete;
   nsAttrAndChildArray& operator=(const nsAttrAndChildArray& aOther) = delete;
@@ -148,7 +151,8 @@ private:
   nsMappedAttributes*
   GetModifiableMapped(nsMappedAttributeElement* aContent,
                       nsHTMLStyleSheet* aSheet,
-                      bool aWillAddAttr);
+                      bool aWillAddAttr,
+                      int32_t aAttrCount = 1);
   nsresult MakeMappedUnique(nsMappedAttributes* aAttributes);
 
   uint32_t AttrSlotsSize() const