Convert cros_sdk to strict sudo non-interactive usage.
Convert cros_sdk to strict sudo non-interactive usage.

This means that the only sudo interactiveness allowed is from
within SudoKeepAlive; any other usage is an immediate failure.

BUG=chromium-os:18393
TEST=cros_sdk --replace

Change-Id: I64e320a6574fd7c35a49c527d55b8bbcef56cbe7
Reviewed-on: https://gerrit.chromium.org/gerrit/15301
Commit-Ready: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>
Reviewed-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>
Tested-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>

coreos/chromite,zhang0137/chromite,chadversary/chromiumos.chromite,zhang0137/chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,zhang0137/chromite,bpsinc-native/src_third_party_chromite