Cleanup the NgIf directive and remove facades.
Cleanup the NgIf directive and remove facades.

I tested the ng_if_test locally since it doesn't run on Blaze yet.

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Created by MOE: https://github.com/google/moe
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matanlurey/angular,kevmoo/angular,chalin/angular2,angulardart/angular,matanlurey/angular,chalin/angular2,kevmoo/angular,kevmoo/angular,angulardart/angular,chalin/angular2,matanlurey/angular,angulardart/angular