Files.app: Remove RootDirectory constant from NavigationListModel class.

NavigationListModel uses RootDirectory.DRIVE to check availability of drive
volume. Currently folder shortcut is loaded only for current profile, so we can
use getCurrentProfileVolumeInfo(RootType.DRIVE) to get proper VolumeInfo.

BUG=302090
TEST=call isDriveMounted from the inspector.
R=yoshiki@chromium.org

Review URL: https://codereview.chromium.org/94013002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237904 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237904
Files.app: Sets real current profile values.

Previously VolumeManager uses fake values as a profile information.  This CL
replace the fake values with the real value obtained by the private API.

BUG=319420
TEST=manually, check the profile value in the inspector.
R=kinaba@chromium.org

Review URL: https://codereview.chromium.org/96423002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237905 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237905