Camera: Dont reset camera state while capture is in progress.

While capture is in progress and if we get autofocus event,
currently we reset the camera state to IDLE blindly. This is
resulting in app exception because it will trigger another
takepicture and lower layers will return error.

( cherrypicked from commit 1bed537bb0848b6a1f64f9eb245b1c256999ebad )

Change-Id: Ia595dbad246759870371b749c0aa2def221560c5
CRs-Fixed: 550417