Minor optimization in ValidatorServiceProvider

ReflectionClass is only needed if a translator is present. Moving usage of it inside the related conditional means one less object instantiation.
minor #978 Minor optimization in ValidatorServiceProvider (elazar)

This PR was merged into the 1.2 branch.

Discussion
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Minor optimization in ValidatorServiceProvider

`ReflectionClass` is only needed if a translator is present. Moving usage of it inside the related conditional means one less object instantiation.

Commits
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1aed8cd Minor optimization in ValidatorServiceProvider