Make storage_monitor a component

Move storage_monitor to the components directory and:

- Make the unit tests part of the components unit tests.
- Update the include headers for both chrome and storage_monitor code.
- Update the buildsystem dependencies and paths.
- Update the DEPS files for both chrome and storage_monitor with the new
restrictions.

R=joi@chromium.org,thestig@chromium.org
BUG=

Review URL: https://codereview.chromium.org/152343005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251699 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251699