fix for GRAILS-6100 "Unable to display a specific view with an additional HandlerExceptionResolver"

Author: graemerocher

src/java/org/codehaus/groovy/grails/web/servlet/GrailsDispatcherServlet.java

@@ -210,6 +210,7 @@ public Locale getLocale() {
         Exception handlerException = null;
         try {
             ModelAndView mv;
+			boolean errorView = false;
             try {
                 Object exceptionAttribute = request.getAttribute(EXCEPTION_ATTRIBUTE);
                 // only process multipart requests if an exception hasn't occured
@@ -279,6 +280,7 @@ public Locale getLocale() {
                 handlerException = ex;
                 Object handler = (mappedHandler != null ? mappedHandler.getHandler() : null);
                 mv = processHandlerException(request, response, handler, ex);
+				errorView = (mv != null);
             }
 
             // Did the handler return a view to render?
@@ -288,6 +290,9 @@ public Locale getLocale() {
 
                 try {
                     render(mv, processedRequest, response);
+					if (errorView) {
+						WebUtils.clearErrorRequestAttributes(request);
+					}
                 } catch (Exception e) {
                     // Only render the error view if we're not already trying to render it.
                     // This prevents a recursion if the error page itself has errors.