public void Waiting_Invalid2 ()
		{
			Console.WriteLine ("Waiting_Invalid2");

			var download = new Download ();
			Assert.Throws<InvalidOperationException> (() => download.Retry ());
		}
		public void Error_Retry ()
		{
			Console.WriteLine ("Error_Retry");

			var download = new Download ();
			bool failed = download.TryFail (404, TaskErrorEnum.DownloadError, "Not Found");
			Assert.AreEqual (true, failed, "Failed");
			download.Retry ();
			Assert.AreEqual (State.Waiting, download.State, "State");
		}
		public void Downloading_Invalid1 ()
		{
			Console.WriteLine ("Downloading_Invalid1");

			var download = new Download ();
			bool resumed = download.TryResume ();
			Assert.AreEqual (true, resumed, "Resumed");
			Assert.Throws<InvalidOperationException> (() => download.Retry ());
		}