chromeos: Remove BrightnessObserver class.

The public accounts hack that was in this class is no longer
needed, and everything else that was in it has been moved to
other classes.

BUG=none

Review URL: https://codereview.chromium.org/27045003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228235 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228235
Remove crash dump counting from breakpad_win.cc to BreakpadClient

BUG=247431
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/26409005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228236 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228236