Fix a bootloop problem when /data/system/usagestats/usage-history.xml is empty.
This often occurs after an incomplete reboot/shutdown or battery pull.
frameworks/base: remove some duplicate ringtones/notification sounds

PS2: Start mk file cleanup
PS3: Remove empty mk files
PS4: Remove more dupes and unused audio

Change-Id: I7a091218e41b3cf7eea9738d9ea569d9cb3ee91d
alarms: clean up duplicated sounds

another mess...

Alarm_Classic == Oxygen == Cesium
Promethium == Platinum
Argon == Fermium
Nobelium == Neon
Helium == Hassium
Plutonium == Krypton
Neptunium == Carbon

Change-Id: I29330a50a2538a5e3cf3af99d4f7bf1b17de7aca