squashed commit from maxwen: true preview

this contains:
https://github.com/maxwen/android_packages_apps_Camera/commit/65e70013413bf4a95d6856ef0e2f30052d39ea17
https://github.com/maxwen/android_packages_apps_Camera/commit/5aa8681355edc067f065904712c65d4253cffbca
...and the final, real nice one...:
https://github.com/maxwen/android_packages_apps_Camera/commit/e4f33d5f771e5e693a113cdc9fabfac0fd1966ff