This lets the user decide what to do (like scrolling)

Instead handle everything throuh property updates.

Instead stop it form outside which gives us more control.

This way we can extend the message with more data in the future if needed.

In case we move it out of view and back again we want a second event. The user can filter those
out if needed.

We need to give feedback to the user, so better let the user decide.

We use it for user feedback now, so there is no good reason to allow disabling it.

This allows us to show feedback to the user by coloring the clip border.
Also in case there is no match we don't send an event.

There is no need to emit the same thing 5 times a second.

fewer confusing callbacks..

We would get two scanning loops both scanning for qr codes. This makes
sure only one loop is active at all times.

This reverts commit 3c5c82f9.

so they can be reused

This API isn't suported in any browser we support, it used to work in
old chrome.