diff --git a/mozilla/extensions/spatialnavigation/src/nsSpatialNavigationUtils.cpp b/mozilla/extensions/spatialnavigation/src/nsSpatialNavigationUtils.cpp
index cdee3245305..5ab8f776811 100755
--- a/mozilla/extensions/spatialnavigation/src/nsSpatialNavigationUtils.cpp
+++ b/mozilla/extensions/spatialnavigation/src/nsSpatialNavigationUtils.cpp
@@ -337,17 +337,6 @@ isArea(nsIContent* content)
   return isContentOfType(content, "area");
 }
 
-PRBool
-isDocument(nsIFrame* frame)
-{
-  nsIContent* content = frame->GetContent();
-
-  if (!content || !content->IsContentOfType(nsIContent::eHTML))
-      return PR_FALSE;
-
-  return isContentOfType(content, "map");
-}
-
 PRBool
 isMap(nsIFrame* frame)
 {