Revert "[4/4] Telephony: Smart Phone Call"

This reverts commit beca1a350b07a7689871d34a87e3e65420518e1d.
Mobile Network Battery Saver Mode

When idle (screen off) switching to 2G can help extend
battery life as 2G generally uses less power than 3G or LTE.

    + 30 seconds after screen turns off, set network type to 2G
    + If a music player is active (playing), do not set network to 2G
    + When device is unlocked, reset to orignial network type

Settings -> More -> Mobile Networks -> Battery saving mode

Change-Id: Ief8f203f157af3a1484966d43fcc07fd160e4ad7
[2/3] Telephony: allow disabling non intrusive incall ui