How are you previewing the app and are you running this in the fiori client? Web IDE has the cordova facade configured within it which allows you to test cordova features in a desktop browser. This wouldn't be available outside of Web IDE without modification. You also have some typos in your code, semicolon next to saveToPhotoAlbum and you are missing a bracket which may be your issue.
Regards,
Jamie
SAP - Technology RIG