[BUG] Embedded videos lack float attribute

[jjsanderson]

Describe the bug
An embedded video, when set to float right or left alongside the following text block, displays correctly in the editor… but does not float in the resulting public page.

To Reproduce
Steps to reproduce the behaviour:

1. Create a post
2. Add a video element, from self-hosted video or an external hosting service.
3. Select 'align text right/left' from the whatever-that-attached-thing-above-the-box is called.
4. Publish the page.
5. View resulting page.

Expected behaviour
Videos should float left/right as images do.

Platform (please complete the following information):

• OS: OS X 10.14.4
• Safari and Chrome, current versions.

Additional context
This looks to me like the styles are simply missing the float right/left attributes in the CSS; if I add them, the page renders as expected.