OpenGL driver: trigger a setRenderStates2DMode() recalc when the screen size...

OpenGL driver: trigger a setRenderStates2DMode() recalc when the screen size changes.  This fixes the OpenGL 2D scaling issue.  Excelsior!

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@1772 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COpenGLDriver.cpp

@@ -2614,6 +2614,7 @@ void COpenGLDriver::OnResize(const core::dimension2d<s32>& size)
 {
 	CNullDriver::OnResize(size);
 	glViewport(0, 0, size.Width, size.Height);
+	Transformation3DChanged = true;
 }