CorsInterceptor skips async dispatch

Closes gh-24223

Author: rstoyanchev

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

@@ -36,6 +36,8 @@
 import org.springframework.util.PathMatcher;
 import org.springframework.web.HttpRequestHandler;
 import org.springframework.web.context.request.WebRequestInterceptor;
+import org.springframework.web.context.request.async.WebAsyncManager;
+import org.springframework.web.context.request.async.WebAsyncUtils;
 import org.springframework.web.context.support.WebApplicationObjectSupport;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.CorsConfigurationSource;
@@ -569,6 +571,12 @@ public CorsInterceptor(@Nullable CorsConfiguration config) {
 		public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
 				throws Exception {
 
+			// Consistent with CorsFilter, ignore ASYNC dispatches
+			WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(request);
+			if (asyncManager.hasConcurrentResult()) {
+				return true;
+			}
+
 			return corsProcessor.processRequest(this.config, request, response);
 		}