diff --git a/layout/generic/nsHTMLParts.h b/layout/generic/nsHTMLParts.h
index a348495dedca..7c53562c6032 100644
--- a/layout/generic/nsHTMLParts.h
+++ b/layout/generic/nsHTMLParts.h
@@ -158,6 +158,14 @@ extern nsresult
 NS_NewTableCaptionPart(nsIHTMLContent** aInstancePtrResult,
                        nsIAtom* aTag);
 
+extern nsresult
+NS_NewHTMLApplet(nsIHTMLContent** aInstancePtrResult,
+                 nsIAtom* aTag);
+
+extern nsresult
+NS_NewHTMLObject(nsIHTMLContent** aInstancePtrResult,
+                 nsIAtom* aTag);
+
 extern nsresult
 NS_NewHTMLImage(nsIHTMLContent** aInstancePtrResult,
                 nsIAtom* aTag);
diff --git a/layout/html/base/src/nsHTMLParts.h b/layout/html/base/src/nsHTMLParts.h
index a348495dedca..7c53562c6032 100644
--- a/layout/html/base/src/nsHTMLParts.h
+++ b/layout/html/base/src/nsHTMLParts.h
@@ -158,6 +158,14 @@ extern nsresult
 NS_NewTableCaptionPart(nsIHTMLContent** aInstancePtrResult,
                        nsIAtom* aTag);
 
+extern nsresult
+NS_NewHTMLApplet(nsIHTMLContent** aInstancePtrResult,
+                 nsIAtom* aTag);
+
+extern nsresult
+NS_NewHTMLObject(nsIHTMLContent** aInstancePtrResult,
+                 nsIAtom* aTag);
+
 extern nsresult
 NS_NewHTMLImage(nsIHTMLContent** aInstancePtrResult,
                 nsIAtom* aTag);