diff --git a/mozilla/content/shared/public/nsLayoutAtomList.h b/mozilla/content/shared/public/nsLayoutAtomList.h
index 29ef10cd00b..7903fbbdc1c 100644
--- a/mozilla/content/shared/public/nsLayoutAtomList.h
+++ b/mozilla/content/shared/public/nsLayoutAtomList.h
@@ -101,6 +101,7 @@ LAYOUT_ATOM(viewportFrame, "ViewportFrame")
 
   // Alphabetical list of frame property names
 LAYOUT_ATOM(overflowProperty, "OverflowProperty")
+LAYOUT_ATOM(maxElementSizeProperty, "MaxElementSizeProperty")
 
 #ifdef DEBUG
   // Alphabetical list of atoms used by debugging code
diff --git a/mozilla/layout/base/nsLayoutAtomList.h b/mozilla/layout/base/nsLayoutAtomList.h
index 29ef10cd00b..7903fbbdc1c 100644
--- a/mozilla/layout/base/nsLayoutAtomList.h
+++ b/mozilla/layout/base/nsLayoutAtomList.h
@@ -101,6 +101,7 @@ LAYOUT_ATOM(viewportFrame, "ViewportFrame")
 
   // Alphabetical list of frame property names
 LAYOUT_ATOM(overflowProperty, "OverflowProperty")
+LAYOUT_ATOM(maxElementSizeProperty, "MaxElementSizeProperty")
 
 #ifdef DEBUG
   // Alphabetical list of atoms used by debugging code
diff --git a/mozilla/layout/base/public/nsLayoutAtomList.h b/mozilla/layout/base/public/nsLayoutAtomList.h
index 29ef10cd00b..7903fbbdc1c 100644
--- a/mozilla/layout/base/public/nsLayoutAtomList.h
+++ b/mozilla/layout/base/public/nsLayoutAtomList.h
@@ -101,6 +101,7 @@ LAYOUT_ATOM(viewportFrame, "ViewportFrame")
 
   // Alphabetical list of frame property names
 LAYOUT_ATOM(overflowProperty, "OverflowProperty")
+LAYOUT_ATOM(maxElementSizeProperty, "MaxElementSizeProperty")
 
 #ifdef DEBUG
   // Alphabetical list of atoms used by debugging code