dock:: fix dock won't hide problem.

the isLauncherShown is wrong.

tower:https://tower.im/projects/8f19f0bf0e754f0b82ef2c24bc230973/todos/b5138dc995e643c09d39015d9c4ff658/
Change-Id: Ie188900b1d7f1eb5f4249163ccbe1db75db80dfc