fix: cover some device selection edge cases

[myandrienko]

This PR fixes some edge cases around device selection:

Selecting the default device

Chrome allows requesting user media with device id default. For the purposes of the SDK, we treat this device as if it didn't existed, and filter it out of device lists. However, it was still possible to select it manually.

Now device id default is filtered out of media requests, so even if it is selected manually, it is replaced with an actual device id when device is unmuted.

Selecting non-existing device id

Previously, selecting non-existing device (e.g. call.camera.select('nonsense')) resulted in the default device being selected. That could be a nasty surprise for a user.

Now, either select method will throw (if device is already unmuted) or enabling the device will throw later.

This takes us to the final change:

Error handler for device selectors

onError callback added to audio and video device selectors, since select method can now throw in a rare case that the device list is stale.