public override void Add(ProviderBase provider)
        {
            Assert.ArgumentNotNull((object)provider, nameof(provider));
            MockLocationFallbackProviderBase provider1 = provider as MockLocationFallbackProviderBase;

            Assert.IsNotNull((object)provider1, "The provider type passed to MockLocationFallbackProviderCollection is not assignable to MockLocationFallbackProviderBase. Actual type: {0}", (object)provider.GetType().FullName);
            this.Add(provider1);
        }
 public virtual void Add(MockLocationFallbackProviderBase provider)
 {
     Assert.ArgumentNotNull((object)provider, nameof(provider));
     base.Add((ProviderBase)provider);
 }