minor #1093 Improve code coverage of SecurityTrait (SofHad)
minor #1093 Improve code coverage of SecurityTrait (SofHad)

This PR was merged into the 1.2 branch.

Discussion
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Improve code coverage of SecurityTrait

Additional tests to cover:
- Empty token: https://github.com/silexphp/Silex/blob/1.2/src/Silex/Application/SecurityTrait.php#L33-35
- Invalid user: https://github.com/silexphp/Silex/blob/1.2/src/Silex/Application/SecurityTrait.php#L37-39

Commits
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9502388 Add tests

cgsmith/Silex,lokhman/Silex,mmauri04/Silex,Xephi/Silex,RayRutjes/Silex,beealone/Silex,romainneutron/Silex,arduanov/Silex,romainneutron/Silex,fabpot/Silex,mTorres/Silex,beealone/Silex,fhinkel/Silex,romainneutron/Silex,jdreesen/Silex,Incognito/silex-fork,Xephi/Silex,cesarmarinhorj/Silex,jdreesen/Silex,SpacePossum/Silex,gencer/Silex,plotek/Silex,SanderKnape/Silex,mathroc/Silex,fabpot/Silex,RayRutjes/Silex,mTorres/Silex,mmauri04/Silex,silexphp/Silex,arduanov/Silex,Incognito/silex-fork,lokhman/Silex,plotek/Silex,SpacePossum/Silex,JPry/Silex,cesarmarinhorj/Silex,JPry/Silex,cgsmith/Silex,fhinkel/Silex,SanderKnape/Silex,mathroc/Silex