symfony/src/Symfony/Bundle/FrameworkBundle/Resources/config/toolbar.xml

<?xml version="1.0" ?>

<container xmlns="http://www.symfony-project.org/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.symfony-project.org/schema/dic/services http://www.symfony-project.org/schema/dic/services/services-1.0.xsd">

    <parameters>
        <parameter key="debug.toolbar.class">Symfony\Components\HttpKernel\Profiler\WebDebugToolbarListener</parameter>
    </parameters>

    <services>
        <service id="debug.toolbar" class="%debug.toolbar.class%">
            <tag name="kernel.listener" />
            <argument type="service" id="profiler" />
        </service>
    </services>
</container>