message: fix context template
diff: @@ -7,7 +7,7 @@ use std::rc::Rc;
  /// Builds a context with dummy OpenGL functions.
  pub fn build_context() -> Rc<glium::backend::Context> {
  unsafe {
  - glium::backend::Context::new::<_, ()>(DummyBackend, false, Default::default()).unwrap()
  + glium::backend::Context::new::<_>(DummyBackend, false, Default::default()).unwrap()
  }
  }
  