Add more methods to DOMWindowLifecycleNotifier/Observer and implement them in DeviceMotionController

BUG=

Review URL: https://chromiumcodereview.appspot.com/22903004

git-svn-id: svn://svn.chromium.org/blink/trunk@156712 bbb929c8-8fbe-4397-9dbb-9b2b20218538