diff -r 000000000000 -r 6474c204b198 layout/xul/nsResizerFrame.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/xul/nsResizerFrame.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,73 @@
+/* -*- 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 nsResizerFrame_h___
+#define nsResizerFrame_h___
+
+#include "mozilla/Attributes.h"
+#include "mozilla/EventForwards.h"
+#include "nsTitleBarFrame.h"
+
+class nsIBaseWindow;
+class nsMenuPopupFrame;
+
+class nsResizerFrame : public nsTitleBarFrame 
+{
+protected:
+  struct Direction {
+    int8_t mHorizontal;
+    int8_t mVertical;
+  };
+
+public:
+  NS_DECL_FRAMEARENA_HELPERS
+
+  friend nsIFrame* NS_NewResizerFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);  
+
+  nsResizerFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
+
+  virtual nsresult HandleEvent(nsPresContext* aPresContext,
+                               mozilla::WidgetGUIEvent* aEvent,
+                               nsEventStatus* aEventStatus) MOZ_OVERRIDE;
+
+  virtual void MouseClicked(nsPresContext* aPresContext,
+                            mozilla::WidgetMouseEvent* aEvent) MOZ_OVERRIDE;
+
+protected:
+  nsIContent* GetContentToResize(nsIPresShell* aPresShell, nsIBaseWindow** aWindow);
+
+  Direction GetDirection();
+
+  /**
+   * Adjust the window position and size in a direction according to the mouse
+   * movement and the resizer direction. The minimum and maximum size is used
+   * to constrain the size.
+   *
+   * @param aPos left or top position
+   * @param aSize width or height
+   * @param aMinSize minimum width or height
+   * @param aMacSize maximum width or height
+   * @param aMovement the amount the mouse was moved
+   * @param aResizerDirection resizer direction returned by GetDirection
+   */
+  static void AdjustDimensions(int32_t* aPos, int32_t* aSize,
+                               int32_t aMinSize, int32_t aMaxSize,
+                               int32_t aMovement, int8_t aResizerDirection);
+
+  struct SizeInfo {
+    nsString width, height;
+  };
+  static void SizeInfoDtorFunc(void *aObject, nsIAtom *aPropertyName,
+                               void *aPropertyValue, void *aData);
+  static void ResizeContent(nsIContent* aContent, const Direction& aDirection,
+                            const SizeInfo& aSizeInfo, SizeInfo* aOriginalSizeInfo);
+  static void MaybePersistOriginalSize(nsIContent* aContent, const SizeInfo& aSizeInfo);
+  static void RestoreOriginalSize(nsIContent* aContent);
+
+protected:
+	nsIntRect mMouseDownRect;
+	nsIntPoint mMouseDownPoint;
+}; // class nsResizerFrame
+
+#endif /* nsResizerFrame_h___ */