am fd117ff2: Doc change: zh-cn translation of Android L overviews. cherrypick from  I56d1ce58e10b83d10d0077cc9dfbeb04f090b861

* commit 'fd117ff2a4a8edd570ccaedd0cd769613ad4ef74':
  Doc change: zh-cn translation of Android L overviews. cherrypick from  I56d1ce58e10b83d10d0077cc9dfbeb04f090b861