Reverting BHV-11591

Issue
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There is not a guarantee that the models passed to the `remove` method exist in the `enyo.Collection`, nor is there a guarantee that the first model in the passed-in array of models is the first model located in the `enyo.Collection`; thus the index derived from this can be incorrect/invalid and is not safe to use.

Fix
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We revert the commits related to BHV-11591.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>