ANGLE: check for out of date swap chain even when size is empty

This allows the XAML swap chain to work properly, as otherwise it never
got a resize after it was passed into ANGLE with an empty size. This is
fixed by upstream commit 3799c3014a9e4ba4a3853c014a7127254ec19d50, so no
patch is necessary for Qt's local copy.

Change-Id: I43b030fa74f6b30c2aa42a36db2031a84eedf60b
Reviewed-by: Oliver Wolff <oliver.wolff@theqtcompany.com>

src/3rdparty/angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp

@@ -203,6 +203,7 @@ egl::Error SurfaceD3D::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
 
     if (width == 0 || height == 0)
     {
+        checkForOutOfDateSwapChain();
         return egl::Error(EGL_SUCCESS);
     }