Fix broken {@docRoot} links

Some {@docRoot} links were followed by a "/" causing links to break.

Bug:
https://code.google.com/p/android/issues/detail?id=174753

Change-Id: Ic5923ee447c55ac2aa95af365ae63425041e4fcf
(cherry picked from commit e0af48d190114afcd0c7a615187fd524aecda512)
11 files changed