Empty context view does not take up space

[raineorshine]

Steps to Reproduce

- A
- B

1. Set the cursor on A.
2. Activate the context view by clicking in the toolbar or hitting option/alt + shift + S.

Current Behavior

B overlaps with the empty context view message of A.

Expected Behavior

B should be rendered after the empty context view message.

The empty context view message should be measured when determining the height of A in the LayoutTree.