diff --git a/core/core.services.yml b/core/core.services.yml
index 5419d85..8e6f77e 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -634,7 +634,7 @@ services:
       - { name: backend_overridable }
   router.builder:
     class: Drupal\Core\Routing\RouteBuilder
-    arguments: ['@router.dumper', '@lock', '@event_dispatcher', '@module_handler', '@controller_resolver', '@access_manager.check_provider', '@cache.default']
+    arguments: ['@router.dumper', '@lock', '@event_dispatcher', '@module_handler', '@controller_resolver', '@access_manager.check_provider']
     tags:
       - { name: needs_destruction }
   menu.rebuild_subscriber:
diff --git a/core/lib/Drupal/Core/Routing/RouteBuilder.php b/core/lib/Drupal/Core/Routing/RouteBuilder.php
index 23f93c7..6112e0c 100644
--- a/core/lib/Drupal/Core/Routing/RouteBuilder.php
+++ b/core/lib/Drupal/Core/Routing/RouteBuilder.php
@@ -8,7 +8,6 @@
 namespace Drupal\Core\Routing;
 
 use Drupal\Component\Discovery\YamlDiscovery;
-use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\Access\CheckProviderInterface;
 use Drupal\Core\Controller\ControllerResolverInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
@@ -109,17 +108,14 @@ class RouteBuilder implements RouteBuilderInterface, DestructableInterface {
    *   The controller resolver.
    * @param \Drupal\Core\Access\CheckProviderInterface $check_provider
    *   The check provider.
-   * @param \Drupal\Core\Cache\CacheBackendInterface $cache
-   *   The cache object.
    */
-  public function __construct(MatcherDumperInterface $dumper, LockBackendInterface $lock, EventDispatcherInterface $dispatcher, ModuleHandlerInterface $module_handler, ControllerResolverInterface $controller_resolver, CheckProviderInterface $check_provider, CacheBackendInterface $cache) {
+  public function __construct(MatcherDumperInterface $dumper, LockBackendInterface $lock, EventDispatcherInterface $dispatcher, ModuleHandlerInterface $module_handler, ControllerResolverInterface $controller_resolver, CheckProviderInterface $check_provider) {
     $this->dumper = $dumper;
     $this->lock = $lock;
     $this->dispatcher = $dispatcher;
     $this->moduleHandler = $module_handler;
     $this->controllerResolver = $controller_resolver;
     $this->checkProvider = $check_provider;
-    $this->cache = $cache;
   }
 
   /**
@@ -148,10 +144,7 @@ public function rebuild() {
     $this->building = TRUE;
 
     $collection = new RouteCollection();
-
-    $module_dirs = $this->moduleHandler->getModuleDirectories();
-    $this->yamlDiscovery = new YamlDiscovery('routing', $module_dirs);
-    foreach ($this->yamlDiscovery->findAll() as $routes) {
+    foreach ($this->getRouteDefinitions() as $routes) {
       // The top-level 'routes_callback' is a list of methods in controller
       // syntax, see \Drupal\Core\Controller\ControllerResolver. These methods
       // should return a set of \Symfony\Component\Routing\Route objects, either
@@ -207,7 +200,6 @@ public function rebuild() {
     $this->dispatcher->dispatch(RoutingEvents::FINISHED, new Event());
     $this->building = FALSE;
 
-    $this->routeCollection = NULL;
     $this->rebuildNeeded = FALSE;
 
     return TRUE;
@@ -227,9 +219,20 @@ public function rebuildIfNeeded() {
    * {@inheritdoc}
    */
   public function destruct() {
-    if ($this->rebuildNeeded) {
-      $this->rebuild();
+    $this->rebuildIfNeeded();
+  }
+
+  /**
+   * Retrieves all defined routes from .routing.yml files.
+   *
+   * @return array
+   *   The defined routes, keyed by provider.
+   */
+  protected function getRouteDefinitions() {
+    if (!isset($this->yamlDiscovery)) {
+      $this->yamlDiscovery = new YamlDiscovery('routing', $this->moduleHandler->getModuleDirectories());
     }
+    return $this->yamlDiscovery->findAll();
   }
 
 }
diff --git a/core/lib/Drupal/Core/Routing/RouteProvider.php b/core/lib/Drupal/Core/Routing/RouteProvider.php
index e16dcb7..86ecbd1 100644
--- a/core/lib/Drupal/Core/Routing/RouteProvider.php
+++ b/core/lib/Drupal/Core/Routing/RouteProvider.php
@@ -117,7 +117,7 @@ public function __construct(Connection $connection, RouteBuilderInterface $route
   public function getRouteCollectionForRequest(Request $request) {
     $path = $this->currentPath->getPath($request);
 
-    return $this->getRoutesByPath($path);
+    return $this->getRoutesByPath(rtrim($path, '/'));
   }
 
   /**
diff --git a/core/modules/field/src/Tests/FieldImportDeleteUninstallTest.php b/core/modules/field/src/Tests/FieldImportDeleteUninstallTest.php
index 08dda90..d71be2e 100644
--- a/core/modules/field/src/Tests/FieldImportDeleteUninstallTest.php
+++ b/core/modules/field/src/Tests/FieldImportDeleteUninstallTest.php
@@ -27,7 +27,6 @@ class FieldImportDeleteUninstallTest extends FieldUnitTestBase {
   protected function setUp() {
     parent::setUp();
     // Module uninstall requires the router and users_data tables.
-    // FieldUnitTestBase already install the router table.
     // @see drupal_flush_all_caches()
     // @see user_modules_uninstalled()
     $this->installSchema('user', array('users_data'));
diff --git a/core/modules/field_ui/field_ui.module b/core/modules/field_ui/field_ui.module
index 24fbf6e..5c2e22f 100644
--- a/core/modules/field_ui/field_ui.module
+++ b/core/modules/field_ui/field_ui.module
@@ -169,14 +169,14 @@ function field_ui_form_node_type_form_submit($form, FormStateInterface $form_sta
  * Implements hook_entity_view_mode_presave().
  */
 function field_ui_entity_view_mode_presave(EntityViewModeInterface $view_mode) {
-  \Drupal::service('router.builder')->rebuild();
+  \Drupal::service('router.builder')->setRebuildNeeded();
 }
 
 /**
  * Implements hook_entity_form_mode_presave().
  */
 function field_ui_entity_form_mode_presave(EntityFormModeInterface $form_mode) {
-  \Drupal::service('router.builder')->rebuild();
+  \Drupal::service('router.builder')->setRebuildNeeded();
 }
 
 /**
diff --git a/core/modules/shortcut/src/Tests/ShortcutLinksTest.php b/core/modules/shortcut/src/Tests/ShortcutLinksTest.php
index 5cb82f4..a59e5d5 100644
--- a/core/modules/shortcut/src/Tests/ShortcutLinksTest.php
+++ b/core/modules/shortcut/src/Tests/ShortcutLinksTest.php
@@ -183,7 +183,7 @@ public function testShortcutLinkChangeRoute() {
     entity_load('view', 'content')->disable()->save();
     /** @var \Drupal\Core\Routing\RouteBuilderInterface $router_builder */
     $router_builder = \Drupal::service('router.builder');
-    $router_builder->rebuild();
+    $router_builder->rebuildIfNeeded();
     $this->drupalGet('admin/content');
     $this->assertResponse(200);
   }
diff --git a/core/modules/views/src/Tests/Plugin/RelationshipJoinTestBase.php b/core/modules/views/src/Tests/Plugin/RelationshipJoinTestBase.php
index 868c4db..5620c0a 100644
--- a/core/modules/views/src/Tests/Plugin/RelationshipJoinTestBase.php
+++ b/core/modules/views/src/Tests/Plugin/RelationshipJoinTestBase.php
@@ -27,7 +27,7 @@
   /**
    * @var \Drupal\user\Entity\User
    */
-  protected $root_user;
+  protected $rootUser;
 
   /**
    * Overrides \Drupal\views\Tests\ViewUnitTestBase::setUpFixtures().
@@ -38,9 +38,8 @@ protected function setUpFixtures() {
     parent::setUpFixtures();
 
     // Create a record for uid 1.
-    $this->installSchema('system', 'sequences');
-    $this->root_user = entity_create('user', array('name' => $this->randomMachineName()));
-    $this->root_user->save();
+    $this->rootUser = entity_create('user', array('name' => $this->randomMachineName()));
+    $this->rootUser->save();
 
     Views::viewsData()->clear();
   }
diff --git a/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php b/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
index 0b00a7c..94a001a 100644
--- a/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
+++ b/core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
@@ -72,13 +72,6 @@ class RouteBuilderTest extends UnitTestCase {
   protected $controllerResolver;
 
   /**
-   * The cache object for our RouteBuilder.
-   *
-   * @var \Drupal\Core\Cache\CacheBackendInterface|\PHPUnit_Framework_MockObject_MockObject
-   */
-  protected $cache;
-
-  /**
    * @var \Drupal\Core\Access\CheckProviderInterface|\PHPUnit_Framework_MockObject_MockObject
    */
   protected $checkProvider;
@@ -87,7 +80,6 @@ protected function setUp() {
     $this->dumper = $this->getMock('Drupal\Core\Routing\MatcherDumperInterface');
     $this->lock = $this->getMock('Drupal\Core\Lock\LockBackendInterface');
     $this->dispatcher = $this->getMock('\Symfony\Component\EventDispatcher\EventDispatcherInterface');
-    $this->cache = $this->getMock('Drupal\Core\Cache\CacheBackendInterface');
     $this->moduleHandler = $this->getMock('Drupal\Core\Extension\ModuleHandlerInterface');
     $this->controllerResolver = $this->getMock('Drupal\Core\Controller\ControllerResolverInterface');
     $this->yamlDiscovery = $this->getMockBuilder('\Drupal\Component\Discovery\YamlDiscovery')
@@ -95,7 +87,7 @@ protected function setUp() {
       ->getMock();
     $this->checkProvider = $this->getMock('\Drupal\Core\Access\CheckProviderInterface');
 
-    $this->routeBuilder = new TestRouteBuilder($this->dumper, $this->lock, $this->dispatcher, $this->moduleHandler, $this->controllerResolver, $this->checkProvider, $this->cache);
+    $this->routeBuilder = new TestRouteBuilder($this->dumper, $this->lock, $this->dispatcher, $this->moduleHandler, $this->controllerResolver, $this->checkProvider);
     $this->routeBuilder->setYamlDiscovery($this->yamlDiscovery);
   }
 
@@ -112,14 +104,6 @@ public function testRebuildLockingUnlocking() {
       ->method('release')
       ->with('router_rebuild');
 
-    $this->moduleHandler->expects($this->once())
-      ->method('getModuleDirectories')
-      ->will($this->returnValue(array()));
-
-    $this->cache->expects($this->once())
-      ->method('getMultiple')
-      ->will($this->returnValue(array()));
-
     $this->yamlDiscovery->expects($this->any())
       ->method('findAll')
       ->will($this->returnValue(array()));
@@ -167,14 +151,6 @@ public function testRebuildWithStaticModuleRoutes() {
       ->method('findAll')
       ->will($this->returnValue(array('test_module' => $routes)));
 
-    $this->moduleHandler->expects($this->once())
-      ->method('getModuleDirectories')
-      ->will($this->returnValue(array('test_module' => 'some/dir')));
-
-    $this->cache->expects($this->once())
-      ->method('getMultiple')
-      ->will($this->returnValue(array()));
-
     $route_collection = $routing_fixtures->sampleRouteCollection();
     $route_build_event = new RouteBuildEvent($route_collection);
 
@@ -248,14 +224,6 @@ public function testRebuildWithProviderBasedRoutes() {
 
     $route_build_event = new RouteBuildEvent($route_collection_filled);
 
-    $this->moduleHandler->expects($this->once())
-      ->method('getModuleDirectories')
-      ->will($this->returnValue(array('test_module' => 'some/dir')));
-
-    $this->cache->expects($this->once())
-      ->method('getMultiple')
-      ->will($this->returnValue(array()));
-
     // Ensure that the alter routes events are fired.
     $this->dispatcher->expects($this->at(0))
       ->method('dispatch')