minor symfony#15775 Update profiler.rst (erickr)

This PR was merged into the 4.4 branch.

Discussion
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Update profiler.rst

the getKernel() method is available in $event rather than $this, however the $event->getKernel() refers to the \Symfony\Component\HttpKernel\HttpKernel which does not have the isDebug()-method.

Perhaps a full event subscriber class could be included to make it more complete?

Same problem applies  on 5.3, 5.4 and 6.0 as well.

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Commits
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02ed37c Update profiler.rst

Author: javiereguiluz

profiler.rst

@@ -195,7 +195,7 @@ event::
 
     public function onKernelResponse(ResponseEvent $event)
     {
-        if (!$this->getKernel()->isDebug()) {
+        if (!$event->getKernel()->isDebug()) {
             return;
         }