Shortcodes: Conflicts with WordPress [Embed] Shortcode

When using the [embed] shortcode for a video, adding paramaters doesn't work when Shortcode Embeds is enabled.

#### Steps to reproduce the issue

1. Enable Shortcode Embeds.
2. Create a post or page and add the [embed] shortcode to the Text editor for a video and include a width parameter like this:

[embed width="100"]https://www.youtube.com/watch?v=Rb0UmrCXxVA[/embed])
3. Publish and view the post or page.
4. Notice that there is no resizing.
5. Disable Shortcode Embeds.
6. Refresh the post or page.
7. Notice that the video resizes.

#### What I expected

I expected the video would resize all the time.

Internal ref: 644194-zen

Begin by tracing Shortcode Embeds handling of the [embed] shortcode in the Jetpack repository. Reproduce the issue with a video URL and width parameter, comparing output with Shortcode Embeds enabled and disabled. Done means the width is honored in both cases.

Written by the indexing model from the issue text.