RequestMatcherDelegatingWebInvocationPrivilegeEvaluator doesn't provided access to the ServletContext

[philwebb]

Describe the bug
See spring-projects/spring-boot#29564 for details.

The recently introduced RequestMatcherDelegatingWebInvocationPrivilegeEvaluator class creates a new FilterInvocation in the getDelegate method. This invocation has a DummyRequest which cannot provide access to the ServletContext. This means that Spring Boot's ApplicationContextRequestMatcher cannot get the WebApplicationContext.

This feels quite similar to #10208 which was fixed by making the WebInvocationPrivilegeEvaluator ServletAware.

To Reproduce
Run tests from the sample application at https://github.com/jeffbswope/null-servletcontext-errorpagefilter

Expected behavior
The tests should pass

Sample
https://github.com/jeffbswope/null-servletcontext-errorpagefilter