Fixing Windows bustage...

gfx/src/windows/nsDeviceContextWin.cpp

@@ -568,6 +568,16 @@ NS_IMETHODIMP nsDeviceContextWin :: GetSystemFont(nsSystemFontID anID, nsFont *a
   return status;
 }
 
+NS_IMETHODIMP nsDeviceContextWin :: GetDrawingSurface(nsIRenderingContext &aContext, nsDrawingSurface &aSurface)
+{
+  if (NULL == mSurface) {
+    aContext.CreateDrawingSurface(nsnull, 0, mSurface);
+  }
+
+  aSurface = mSurface;
+  return NS_OK;
+}
+
 int CALLBACK fontcallback(ENUMLOGFONT FAR *lpelf, NEWTEXTMETRIC FAR *lpntm,
                           int FontType, LPARAM lParam)  
 {

gfx/src/windows/nsDeviceContextWin.h

@@ -63,6 +63,12 @@ public:
   NS_IMETHOD  GetScrollBarDimensions(float &aWidth, float &aHeight) const;
   NS_IMETHOD  GetSystemFont(nsSystemFontID anID, nsFont *aFont) const;
 
+  //get a low level drawing surface for rendering. the rendering context
+  //that is passed in is used to create the drawing surface if there isn't
+  //already one in the device context. the drawing surface is then cached
+  //in the device context for re-use.
+  NS_IMETHOD  GetDrawingSurface(nsIRenderingContext &aContext, nsDrawingSurface &aSurface);
+
   NS_IMETHOD  CheckFontExistence(const nsString& aFontName);
 
   NS_IMETHOD  GetDepth(PRUint32& aDepth);

gfx/src/windows/nsImageWin.cpp

@@ -40,7 +40,7 @@
 
 #include "nsImageWin.h"
 #include "nsRenderingContextWin.h"
-
+#include "nsDeviceContextWin.h"
 
 static nsresult BuildDIB(LPBITMAPINFOHEADER  *aBHead,PRInt32 aWidth,PRInt32 aHeight,PRInt32 aDepth,PRInt8  *aNumBitPix);
 
@@ -554,7 +554,8 @@ nsImageWin :: Draw(nsIRenderingContext &aContext, nsDrawingSurface aSurface,
       nsIDeviceContext    *dx;
       aContext.GetDeviceContext(dx);
       nsDrawingSurface     ds;
-      dx->GetDrawingSurface(aContext, ds);
+      
+      NS_STATIC_CAST(nsDeviceContextWin*, dx)->GetDrawingSurface(aContext, ds);
       nsDrawingSurfaceWin *srcDS = (nsDrawingSurfaceWin *)ds;
       HDC                 srcDC;