mash: Move ash_switches.* to ash/common; cleanup DEPS.

tools/git/move_source_file.py ash/ash_switches* ash/common/
Fix include in ash/virtual_keyboard_controller_unittest.cc.
Remove explicit ash_switches.h entry from ash/common/DEPS.

BUG=619636
TEST=Compiles, no changes.
R=jamescook@chromium.org,sky@chromium.org
TBR=stevenjb@chromium.org

Review-Url: https://codereview.chromium.org/2074213002
Cr-Commit-Position: refs/heads/master@{#400485}
96 files changed