Minor updates in HandlerMappingIntrospector

Required by Spring Security to complete work on
spring-projects/spring-security#14128

The setCache and resetCache methods used from createCacheFilter are now
public. Generally they don't need to be used outside of the Filter if
only making checks against the current request. Spring Security, however,
makes additional checks against requests with alternative paths.

spring-webmvc/src/main/java/org/springframework/web/servlet/handler/HandlerMappingIntrospector.java

@@ -191,8 +191,12 @@ public List<HandlerMapping> getHandlerMappings() {
 	public Filter createCacheFilter() {
 		return (request, response, chain) -> {
 			CachedResult previous = setCache((HttpServletRequest) request);
-			chain.doFilter(request, response);
-			resetCache(request, previous);
+			try {
+				chain.doFilter(request, response);
+			}
+			finally {
+				resetCache(request, previous);
+			}
 		};
 	}
 
@@ -206,7 +210,7 @@ public Filter createCacheFilter() {
 	 * @since 6.0.14
 	 */
 	@Nullable
-	private CachedResult setCache(HttpServletRequest request) {
+	public CachedResult setCache(HttpServletRequest request) {
 		CachedResult previous = (CachedResult) request.getAttribute(CACHED_RESULT_ATTRIBUTE);
 		if (previous == null || !previous.matches(request)) {
 			HttpServletRequest wrapped = new AttributesPreservingRequest(request);
@@ -245,7 +249,7 @@ private CachedResult setCache(HttpServletRequest request) {
 	 * a filter after delegating to the rest of the chain.
 	 * @since 6.0.14
 	 */
-	private void resetCache(ServletRequest request, @Nullable CachedResult cachedResult) {
+	public void resetCache(ServletRequest request, @Nullable CachedResult cachedResult) {
 		request.setAttribute(CACHED_RESULT_ATTRIBUTE, cachedResult);
 	}
 
@@ -363,7 +367,7 @@ private <T> T doWithHandlerMapping(
 	 * @since 6.0.14
 	 */
 	@SuppressWarnings("serial")
-	private static final class CachedResult {
+	public static final class CachedResult {
 
 		private final DispatcherType dispatcherType;