IpAddressServerWebExchangeMatcher throws NullPointerException with framework forward-headers-strategy

[dsbecker]

Describe the bug
When server.forward-headers-strategy=framework is used in a WebFlux project that makes use of an IpAddressServerWebExchangeMatcher a NullPointerException is thrown when a Forwarded or X-Forwarded-For header is present because the remoteAddress created by ForwardedHeaderTransformer is unresolved.

To Reproduce

1. Create a sample WebFlux project and set server.forward-headers-strategy=framework
2. Define a SecurityWebFilterChain bean that calls an IpAddressServerWebExchangeMatcher
3. Submit a request with a Forwarded or X-Forwarded-For header

Expected behavior
The IpAddressServerWebExchangeMatcher should execute as normal with no exception thrown.

Sample
server.forward-headers-strategy=framework

    @Bean
    public SecurityWebFilterChain springSecurityFilterChain(ServerHttpSecurity httpSecurity) {
        return httpSecurity
                .authorizeExchange(auth -> auth
                        .pathMatchers("/**")
                            .access((authentication, authorizationContext) ->
                                new IpAddressServerWebExchangeMatcher("255.255.255.255")
                                        .matches(authorizationContext.getExchange())
                                        .map(matchResult -> new AuthorizationDecision(matchResult.isMatch()))))
                .build();
    }

[dsbecker]

Submitted PR to fix this: #11889

[jzheaux]

Closed in 2b42687