Remove horizontal scrollbar and change event name to follow conventions
minor #4317 Remove horizontal scrollbar and change event name to follow conventions (ifdattic)

This PR was merged into the 2.3 branch.

Discussion
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Remove horizontal scrollbar and change event name to follow conventions

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.3
| Fixed tickets |

In my opinion the event name should follow the naming conventions http://symfony.com/doc/current/components/event_dispatcher/introduction.html#naming-conventions

Commits
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7fe8a36 Remove horizontal scrollbar and change event name to follow conventions