CallInProgressActivity.java should turn screen off onProximity

[lukeweber]

Because of the samsung galaxy ace, we don't turn the screen off. Basically, after testing a bit more, I'm pretty sure there are more phones that violate this, but I've so far only found the galaxy ace.

Instead of debasing battery life for all compliant phones, I think it's a better policy to turn off the screen in the way that works on most and not turn it off for a known non-compliant phone.

// Samsung Galaxy Ace locks if you turn the screen off.
params.screenBrightness = 0.01f;

[lukeweber]

We could also test whether the undocumented, but seemingly available PROXIMITY_WAKE_LOCK would work as standard and this method as a fallback.

http://stackoverflow.com/questions/3018716/android-turn-off-screen-when-close-to-face

[lukeweber]

Can also see reference code in PhoneApp https://android.googlesource.com/platform/packages/apps/Phone/+/5bcbca1162b1b462d15ebb4a5b2859a076d382e2/src/com/android/phone/PhoneApp.java