[EasyUnlock] Add a private API for establishing an insecure Bluetooth connection.
This is needed to avoid a pairing request prompt when connecting to a service on
a system that tries to upgrade the connection from general bonding to general
bonding with MITM protection, which according to Android and ChromeOS Bluetooth
experts is the correct behavior.
BUG=403069
TEST=chrome.easyUnlockPrivate.connectToBluetoothServiceInsecurely() should work
just like chrome.bluetoothSocket.connect(), but not show a pairing request
prompt when pairing with Android L.
R=tengs@chromium.org, keybuk@chromium.org
Review URL: https://codereview.chromium.org/
491753002
Cr-Commit-Position: refs/heads/master@{#291353}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@291353 0039d316-1c4b-4281-b951-d872f2087c98