Unit test for empty Access-Control-Request-Headers (Chrome 52)

Includes optimized method/header resolution in CorsConfiguration.

Issue: SPR-14617

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

@@ -64,8 +64,7 @@ import org.springframework.web.util.UrlPathHelper;
  * @see #setInterceptors
  * @see org.springframework.web.servlet.HandlerInterceptor
  */
-public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
-		implements HandlerMapping, Ordered {
+public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport implements HandlerMapping, Ordered {
 
 	private int order = Integer.MAX_VALUE;  // default: same as non-Ordered
 
@@ -236,6 +235,7 @@ public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
 		return this.corsConfigSource.getCorsConfigurations();
 	}
 
+
 	/**
 	 * Initializes the interceptors.
 	 * @see #extendInterceptors(java.util.List)
@@ -339,6 +339,7 @@ public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
 		return (count > 0 ? mappedInterceptors.toArray(new MappedInterceptor[count]) : null);
 	}
 
+
 	/**
 	 * Look up a handler for the given request, falling back to the default
 	 * handler if no specific one is found.
@@ -480,9 +481,7 @@ public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
 		}
 
 		@Override
-		public void handleRequest(HttpServletRequest request, HttpServletResponse response)
-				throws IOException {
-
+		public void handleRequest(HttpServletRequest request, HttpServletResponse response) throws IOException {
 			corsProcessor.processRequest(this.config, request, response);
 		}
 
@@ -502,8 +501,8 @@ public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
 		}
 
 		@Override
-		public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
-				Object handler) throws Exception {
+		public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
+				throws Exception {
 
 			return corsProcessor.processRequest(this.config, request, response);
 		}