[BUGFIX beta] Add context property to itemViews created by collection view

This partially addresses #3086.

I've conditionally added the context property to each of the childViews created by a collection view. After adding this property, one test was breaking. 

This test was ` #each accepts a name binding and does not change the context ` and I fixed that by adding the conditional around the addition of context to the itemView. 

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