Android: Make sure we check and clear exceptions from the camera.

In several places we where ignoring the fact that we might get an
exception from the camera code on Android. Failing to clear them will
cause the application to to terminate.

Task-number: QTBUG-39425
Change-Id: Idfe40e1749f54d551d37dae25912d9ddbc3da01e
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>