Remove HttpRequestPathHelper

The use of the undecoded URL path by default and the removal of suffix
pattern matching effectively means HttpRequestPathHelper is no longer
needed.

Issue: SPR-15640, SPR-15639

spring-webflux/src/test/resources/org/springframework/web/reactive/handler/map.xml

@@ -4,7 +4,6 @@
 		xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">	
 	
 	<bean id="mapping" class="org.springframework.web.reactive.handler.SimpleUrlHandlerMapping">
-		<property name="urlDecode" value="true" />
 		<property name="mappings">
 			<value>
 				welcome.html=mainController