base: cleanup duplicate sound files

http://jira.omnirom.org/browse/OMNI-56
http://jira.omnirom.org/browse/OMNI-262

Change-Id: I42b39ed18864abbb5fddcd099446d766e1961439
Merge "base: cleanup duplicate sound files" into android-4.4
Merge remote-tracking branch 'cm/android-4.4' into android-4.4