Currently, we filter BLE scan results by RSSI to ensure that we do not look for scan results that are physically too far from the current device to support a mobile hotspot. However, this filter was not strictly necessary since if the tether host device truly is out of range of the Chrome OS device, the connection will not actually succeed.

sonnysasaka@ discovered that filtering by RSSI actually causes the kernel to toggle scans on and off frequently, which results in slower Bluetooth performance and may actually be the cause of race conditions which have hampered our Bluetooth performance. Since this filter is not actually necessary, we should remove to improve Bluetooth stability.