Adding MacBook Pro accelerometer support.

A class for handling Sudden Motion Sensors. It's only compiled under Mac OS.

Landing for Leandro Gracia Gil <leandrogracia@google.com>.
Original code review: http://codereview.chromium.org/3169040/show

BUG=44654
TEST=none

Review URL: http://codereview.chromium.org/3187025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57521 0039d316-1c4b-4281-b951-d872f2087c98
4 files changed