Return true on successful accessiblity action click/long click.

1. If a view is clickable or long clickable perfroming the corresponding
   accessiblity action should return true no matter whether there is a
   registered on click/long click listener. Currently true is returned
   only if there is a listener but it is also possible that a sub-class
   overrides performClick and does work there. For example CompoundButton.
   Now if the view is clickable or long clickable we will call the
   perfrom* method and return true, which is we clicked.

2. Fixed some JavaDoc indentation.

bug:7318777

Change-Id: Id603fee378b8f7d07f1128b5641ede57640bab53