Complete fix for BZ 69285. Optimize creation of ParameterMap

Based on sample code and test cases provided by John Engebretson

Author: markt-asf

java/org/apache/catalina/core/ApplicationHttpRequest.java

@@ -732,7 +732,12 @@ void parseParameters() {
             return;
         }
 
-        parameters = new ParameterMap<>(getRequest().getParameterMap());
+        Map<String,String[]> requestParameters = getRequest().getParameterMap();
+        if (requestParameters instanceof ParameterMap<String,String[]>) {
+            parameters = new ParameterMap<>((ParameterMap<String,String[]>) requestParameters);
+        } else {
+            parameters = new ParameterMap<>(requestParameters);
+        }
         mergeParameters();
         ((ParameterMap<String,String[]>) parameters).setLocked(true);
         parsedParams = true;

webapps/docs/changelog.xml

@@ -123,6 +123,11 @@
         attribute value will also be used by the default and WebDAV Servlets.
         (remm)
       </update>
+      <fix>
+        <bug>69285</bug>: Optimise the creation of the parameter map for
+        included requests. Based on sample code and test cases provided by John
+        Engebretson. (markt)
+      </fix>
       <fix>
         <bug>69527</bug>: Avoid rare cases where a cached resource could be set
         with 0 content length, or could be evicted immediately. (remm)