Remove additionalParams and update RequestActionTrait tests.

The additionalParams parameter isn't very useful as it simply gets
merged into the request later on. We can easily do that earlier in the
process now.

Fix incorrectlty dispatched array based requestAction() calls. They were
going back through Router::parse() when they did not need to.

src/Routing/Dispatcher.php

@@ -94,8 +94,8 @@ public function getEventManager() {
  * @return string|void if `$request['return']` is set then it returns response body, null otherwise
  * @throws \Cake\Controller\Error\MissingControllerException When the controller is missing.
  */
-	public function dispatch(Request $request, Response $response, array $additionalParams = array()) {
-		$beforeEvent = new Event('Dispatcher.beforeDispatch', $this, compact('request', 'response', 'additionalParams'));
+	public function dispatch(Request $request, Response $response) {
+		$beforeEvent = new Event('Dispatcher.beforeDispatch', $this, compact('request', 'response'));
 		$this->getEventManager()->dispatch($beforeEvent);
 
 		$request = $beforeEvent->data['request'];

src/Routing/RequestActionTrait.php

@@ -16,7 +16,7 @@
 use Cake\Core\Configure;
 use Cake\Network\Request;
 use Cake\Network\Response;
-use Cake\Routing\Dispatcher;
+use Cake\Routing\DispatcherFactory;
 use Cake\Routing\Router;
 
 /**
@@ -95,19 +95,23 @@ public function requestAction($url, array $extra = array()) {
 		}
 		unset($extra['post'], $extra['query']);
 
-		if (is_string($url) && strpos($url, Configure::read('App.fullBaseUrl')) === 0) {
-			$url = Router::normalize(str_replace(Configure::read('App.fullBaseUrl'), '', $url));
+		$baseUrl = Configure::read('App.fullBaseUrl');
+		if (is_string($url) && strpos($url, $baseUrl) === 0) {
+			$url = Router::normalize(str_replace($baseUrl, '', $url));
 		}
 		if (is_string($url)) {
 			$params = [
 				'url' => $url
 			];
 		} elseif (is_array($url)) {
-			$params = array_merge($url, [
-				'pass' => [],
+			$params = [
+				'params' => $url,
 				'base' => false,
 				'url' => Router::reverse($url)
-			]);
+			];
+			if (empty($params['params']['pass'])) {
+				$params['params']['pass'] = [];
+			}
 		}
 		if (!empty($post)) {
 			$params['post'] = $post;
@@ -116,8 +120,9 @@ public function requestAction($url, array $extra = array()) {
 			$params['query'] = $query;
 		}
 		$request = new Request($params);
-		$dispatcher = new Dispatcher();
-		$result = $dispatcher->dispatch($request, new Response(), $extra);
+		$request->addParams($extra);
+		$dispatcher = DispatcherFactory::create();
+		$result = $dispatcher->dispatch($request, new Response());
 		Router::popRequest();
 		return $result;
 	}

tests/TestCase/Routing/RequestActionTraitTest.php

@@ -16,6 +16,7 @@
 use Cake\Core\App;
 use Cake\Core\Configure;
 use Cake\Core\Plugin;
+use Cake\Routing\DispatcherFactory;
 use Cake\Routing\RequestActionTrait;
 use Cake\Routing\Router;
 use Cake\TestSuite\TestCase;
@@ -40,9 +41,20 @@ public function setUp() {
 		parent::setUp();
 		Configure::write('App.namespace', 'TestApp');
 		Configure::write('Security.salt', 'not-the-default');
+		DispatcherFactory::add('RoutingFilter');
 		$this->object = $this->getObjectForTrait('Cake\Routing\RequestActionTrait');
 	}
 
+/**
+ * teardown
+ *
+ * @return void
+ */
+	public function tearDown() {
+		parent::tearDown();
+		DispatcherFactory::clear();
+	}
+
 /**
  * testRequestAction method
  *