Fix S2683 FP: Nullable<bool> ?? false

[YairHalberstadt]

Repro steps

Install SonarAnalyzer.CSharp and compile the following code:

using System;

class Program
{
	static void Main(string[] args)
	{
		var obj = args.Length > 0 ? new Program() : null;

		if (obj?.Cond ?? false)
		{
			Console.WriteLine("Foo");
			Console.WriteLine("Bar");
		}
	}

	private bool Cond = new Random().Next() % 2 == 1;
}

Expected behavior

No warning

Actual behavior

Warning S2583 on line 9:

Change this condition so that it does not always evaluate to 'false'; some subsequent code is never executed.

Related information

#152 and #162 are similar, but have been fixed

[andrei-epure-sonarsource]

fixed in #2497