Fix tom-englert#3: Calling CloseSplashScreen has no effect when called before the splash screen is shown

Author: tom-englert

SplashScreen/SplashScreenAdapter.cs

@@ -35,6 +35,9 @@ public class SplashScreenAdapter
 
         internal SplashScreenAdapter(string splashBitmapResourceName, double minimumVisibilityDuration, double fadeoutDuration)
         {
+            if (_splashScreenCloseRequested)
+                return;
+
             _minimumVisibilityDuration = minimumVisibilityDuration;
             _fadeoutDuration = fadeoutDuration;