Add workaround for current tooling

We don't want to put this in one of the product assemblies because that
would undo the API review xD

src/Components/test/testassets/BasicTestApp/BindMethods.cs

@@ -0,0 +1,11 @@
+namespace Microsoft.AspNetCore.Components
+{
+    // This is a temporary workaround for the fact that public previews of VS look for
+    // this type. Without this the tooling won't understand bind or event handlers.
+    //
+    // This has already gotten better in 16.3 and we look for IComponent rather
+    // than specific implementation details.
+    public static class BindMethods
+    {
+    }
+}