Thumbnails do not respect ImageView's scale type

[sjudd]

Primary requests set their transformation based on the ImageView's scale type if the caller didn't manually set a transformation. However if the primary has one or more thumbnails with unset transformations, those thumbnails do not also do so.

It probably makes sense to have both thumbnails and primarys that don't have manually specified transformations inherit transformations based on the view's scale type.

See also #3775

[shenguojun]

Is there any update?