[Fix #204] Update out-dated comments

This PR is self-explanatory.

Author: Andrew Or <andrewor14@gmail.com>

Closes #381 from andrewor14/master and squashes the following commits:

3e8dde2 [Andrew Or] Fix comments for #204
(cherry picked from commit c2d160fbee2ef90a7683d9771f2f632b68d74aef)

Signed-off-by: Patrick Wendell <pwendell@gmail.com>