Fix for Bug 534918's bustage (build error: "initialization of 'OSVal' is skipped by 'default' label")

gfx/src/thebes/nsThebesDeviceContext.cpp

@@ -646,11 +646,12 @@ nsThebesDeviceContext::SetDPI()
                 break;
 #ifdef XP_WIN
             case gfxASurface::SurfaceTypeWin32:
-            case gfxASurface::SurfaceTypeWin32Printing:
+            case gfxASurface::SurfaceTypeWin32Printing: {
                 PRInt32 OSVal = GetDeviceCaps(GetPrintHDC(), LOGPIXELSY);
                 dpi = 144;
                 mPrintingScale = float(OSVal) / dpi;
                 break;
+            }
 #endif
 #ifdef XP_OS2
             case gfxASurface::SurfaceTypeOS2: