wifi: show devices behind a firewall that are connected to the  WiFi hotspot

* Clients that are behind a firewall, in particular Windows-PCs tend
to not respond to the request invoked by the isReached(val)-method.
Executing a ping instead and evaluating the outcome enables us to
bypass the firewall.

Change-Id: If857545c7a4d5fbc9d2dc919096a9c84e64d6877
ProximitySensor: check for correct MaxRange value

Use TYPICAL_PROXIMITY_THRESHOLD for devices that returns incorrect mProximitySensor.getMaximumRange() value;

Presto's proximity sensor returns values: 0.0f(near) or 5.0f(far).
mProximitySensor.getMaximumRange() must return proximity sensor's availible range, but it always return 0, so mProximityThreshold is also 0.

So boolean positive = distance >= 0.0f && distance < mProximityThreshold;  positive will never be
true.
The cause of this problem is proprietary sensor.msm8660.so, it must set proper Range and Resolution for proximity sensor.

Change-Id: I0cf81fd20f210115cbd6db10c0070b12f1c57336
Merge branch 'kitkat3' of https://github.com/shaheerkv/android_frameworks_base into kitkat3