Prevent users from trying to send videos that exceed the size limit.
Also, this commit properly populates height/width on media shared into
the app.
Fixes#8573
Update our media send flow to allow users to send multiple images/videos
at once. This change includes:
- New in-app media picker flow.
- Ability to caption images and videos.
- Image editing tools are made more prominent in the flow.
- Some fixes to the image editing tools.
