Repro Steps:

1) Create a Page
2) Create a Component and put some Elements inside of it that are nice and visible.
3) Introduce the Component to the Page created in Step 1). At this point, it should be visible on-Stage.
4) From the Assets panel, identify the Component created in Step 2), and delete it.

Observe how the Component is still visible on-Stage even though it doesn't exist anymore.

5) Close the Page's tab, and then re-open it.

Observe how the Component is no longer visible on-screen.

Expected Results: Components that are deleted from the Assets should not be present on-Stage when removed, as they don't exist anymore.
Expected Results: Components that are deleted from the Assets should remain in place where they are used, but without any display of the content originally within them. In these cases, the Component's 'Source' Property can either be left to the old URI, or cleared.