[NaCl SDK] nacl_io: Rename Mount -> Filesystem, MountNode -> Node.

(This basically renames everything...)

BUG=none
R=noelallen@chromium.org, sbc@chromium.org

Review URL: https://codereview.chromium.org/113123003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240799 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240799
Build fix

TBR=asargent
BUG=328441

Review URL: https://codereview.chromium.org/115493003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240800 0039d316-1c4b-4281-b951-d872f2087c98
Removing GetDefaultProfile from AshSystemTrayDelegate and browser tests

BUG=322682
TEST=covered by existing unit tests

Review URL: https://codereview.chromium.org/113753006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240801 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240801