Use range-based for loops in DeviceManager.

BUG=none
TEST=none

Change-Id: I22dc0368a6c622086aca448571845391527dc4fd
Reviewed-on: https://chromium-review.googlesource.com/491047
Commit-Ready: Lei Zhang <thestig@chromium.org>
Tested-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed