diff -r 000000000000 -r 6474c204b198 layout/forms/nsSelectsAreaFrame.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/forms/nsSelectsAreaFrame.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef nsSelectsAreaFrame_h___
+#define nsSelectsAreaFrame_h___
+
+#include "mozilla/Attributes.h"
+#include "nsBlockFrame.h"
+
+class nsSelectsAreaFrame : public nsBlockFrame
+{
+public:
+  NS_DECL_FRAMEARENA_HELPERS
+
+  friend nsIFrame* NS_NewSelectsAreaFrame(nsIPresShell* aShell, nsStyleContext* aContext, nsFrameState aFlags);
+
+  virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
+                                const nsRect&           aDirtyRect,
+                                const nsDisplayListSet& aLists) MOZ_OVERRIDE;
+
+  void BuildDisplayListInternal(nsDisplayListBuilder*   aBuilder,
+                                const nsRect&           aDirtyRect,
+                                const nsDisplayListSet& aLists);
+
+  virtual nsresult Reflow(nsPresContext*           aCX,
+                          nsHTMLReflowMetrics&     aDesiredSize,
+                          const nsHTMLReflowState& aReflowState,
+                          nsReflowStatus&          aStatus) MOZ_OVERRIDE;
+
+  nscoord HeightOfARow() const { return mHeightOfARow; }
+  
+protected:
+  nsSelectsAreaFrame(nsStyleContext* aContext) :
+    nsBlockFrame(aContext),
+    mHeightOfARow(0)
+  {}
+
+  // We cache the height of a single row so that changes to the "size"
+  // attribute, padding, etc. can all be handled with only one reflow.  We'll
+  // have to reflow twice if someone changes our font size or something like
+  // that, so that the heights of our options will change.
+  nscoord mHeightOfARow;
+};
+
+#endif /* nsSelectsAreaFrame_h___ */