Blocks don't display in node preview mode

Problem/Motivation

Blocks added to a content context that triggers on content type are not displayed when an editor clicks on the preview button while editing a node.

Steps to reproduce

1. Create a view block
2. Add that view block to a context, then limit that context to your content type.
3. Create a new node, hit the preview button. The block will not display.
4. View the published node, the block will display.

For the time being, we removed the block from context, instead adding the block using the normal core block placement interface. In the normal block interface, we limited the visibility to the content type. In this case the block DOES display in both the node and on the preview page.

My expectation would be that blocks loaded via context would act the same way.