Android: fix registering recorded videos with the Android media scanner

Change-Id: I6dfc4e13b8a0bccb1bcfead728f7e1ddb7b58bb4
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
Android: fix crash when stopping the camera while a recording is active

When unloading the camera, any active recording is automatically
stopped, which in turn triggers the viewfinder to be restarted...
We don't try anymore to restart the viewfinder after stopping recording
unless the camera is still active.

Change-Id: I77e4e3fc8d7116ac660d8bb23f6c400ebed4ffed
Reviewed-by: Christian Stromme <christian.stromme@digia.com>