This patch aims to implement roughly what was in the 2.8 mockups: https://developer.blender.org/T57234#617574. However, as far as i know there's no proper design defined yet.
Currently it's only possible to view the scene's active camera. This Patch solves this by allowing the view3d.view_camera operator to switch to any camera. It makes use of the view3d.camera property which is used for the use_local_camera functionality, this is also to be discussed...
{F8817477}