Made the Direct2D validate after painting

modules/juce_gui_basics/native/juce_win32_Windowing.cpp

@@ -1967,6 +1967,7 @@ private:
                 direct2DContext->clipToRectangle (rectangleFromRECT (r));
                 handlePaint (*direct2DContext);
                 direct2DContext->end();
+                ValidateRect (hwnd, &r);
             }
         }
         else