merged branch fabpot/random-leaks (PR #8948)

This PR was merged into the 2.2 branch.

Discussion
----------

Fixed some random leaks

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

Commits
-------

970405f fixed some circular references

src/Symfony/Component/HttpKernel/DataCollector/RouterDataCollector.php

@@ -50,6 +50,8 @@ class RouterDataCollector extends DataCollector
                 $this->data['route'] = $this->guessRoute($request, $this->controllers[$request]);
             }
         }
+
+        unset($this->controllers[$request]);
     }
 
     protected function guessRoute(Request $request, $controller)

src/Symfony/Component/HttpKernel/EventListener/ProfilerListener.php

@@ -135,6 +135,8 @@ class ProfilerListener implements EventSubscriberInterface
 
         if ($master) {
             $this->saveProfiles($profile);
+
+            unset($this->children);
         }
     }