chameleon: Add is_enabled method to BluetoothController

Let BluetoothController query the state of bluetooth module from
chameleond proxy.

BUG=chromium:476860
TEST=not used yet

Change-Id: I7516ec6055b822f01082e077695fc3a5e75b1d09
Reviewed-on: https://chromium-review.googlesource.com/274336
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
Commit-Queue: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
1 file changed