[tools] Enable the register-protocols optimization when the interpret…

…er is enabled. Fixes #21782. (#21786)

In .NET we don't support loading assemblies at runtime (from outside the app
bundle), which means that we should also be able to enable the
register-protocol optimization when the interpreter is enabled (because we
know all the relevant assemblies at built time).

Fixes #21782.

tests/monotouch-test/ObjCRuntime/RegistrarTest.cs

@@ -5542,8 +5542,6 @@ public void RefEnumValues ()
 		[Test]
 		public void ProtocolsTrimmedAway ()
 		{
-			TestRuntime.AssertNotInterpreter ("This test does not work in the interpreter: https://github.com/xamarin/xamarin-macios/issues/21782");
-
 			PreserveIUIApplicationDelegate (null);
 
 			// A little indirection to try to make the trimmer not be helpful and preserve all the methods on IUIApplicationDelegate.

tools/common/Optimizations.cs

@@ -262,10 +262,10 @@ public void Initialize (Application app, out List<ProductException> messages)
 				OptimizeBlockLiteralSetupBlock = app.Registrar == RegistrarMode.Static || app.Registrar == RegistrarMode.ManagedStatic;
 			}
 
-			// We will register protocols if the static registrar is enabled and loading assemblies is not possible
+			// We will register protocols if the static registrar is enabled
 			if (!RegisterProtocols.HasValue) {
 				if (app.Platform != ApplePlatform.MacOSX || app.XamarinRuntime == XamarinRuntime.NativeAOT) {
-					RegisterProtocols = (app.Registrar == RegistrarMode.Static || app.Registrar == RegistrarMode.ManagedStatic) && !app.UseInterpreter;
+					RegisterProtocols = (app.Registrar == RegistrarMode.Static || app.Registrar == RegistrarMode.ManagedStatic);
 				} else {
 					RegisterProtocols = false;
 				}