bug symfony#14916 [WebProfilerBundle] Added tabindex="-1" to not interfer with normal UX (drAlberT)

This PR was submitted for the 2.7 branch but it was merged into the 2.3 branch instead (closes symfony#14916).

Discussion
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[WebProfilerBundle] Added tabindex="-1" to not interfer with normal UX

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

Commits
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53cdb1a [WebProfilerBundle] Added tabindex="-1" to not interfer with normal UX

Author: fabpot

src/Symfony/Bundle/WebProfilerBundle/Resources/views/Profiler/toolbar.html.twig

@@ -1,7 +1,7 @@
 <!-- START of Symfony Web Debug Toolbar -->
 {% if 'normal' != position %}
     <div id="sfMiniToolbar-{{ token }}" class="sf-minitoolbar" data-no-turbolink>
-        <a href="javascript:void(0);" title="Show Symfony toolbar" onclick="
+        <a href="javascript:void(0);" title="Show Symfony toolbar" tabindex="-1" accesskey="D" onclick="
             var elem = this.parentNode;
             if (elem.style.display == 'none') {
                 document.getElementById('sfToolbarMainContent-{{ token }}').style.display = 'none';
@@ -36,7 +36,7 @@
     {% endfor %}
 
     {% if 'normal' != position %}
-        <a class="hide-button" title="Close Toolbar" onclick="
+        <a class="hide-button" title="Close Toolbar" tabindex="-1" accesskey="D" onclick="
             var p = this.parentNode;
             p.style.display = 'none';
             (p.previousElementSibling || p.previousSibling).style.display = 'none';