Revert "Treat default value that wasn't found as empty value."

This reverts commit 705b64c61127d82bcba2c0920d9a793a5be3bbca.
Base: fix MultiSelectListPreference NPE

Error AndroidRuntime 25851  Caused by: java.lang.NullPointerException
Error AndroidRuntime 25851         at android.preference.MultiSelectListPreference.onGetDefaultValue(MultiSelectListPreference.java:212)
Error AndroidRuntime 25851         at android.preference.Preference.<init>(Preference.java:268)
Error AndroidRuntime 25851         at android.preference.DialogPreference.<init>(DialogPreference.java:69)
Error AndroidRuntime 25851         at android.preference.DialogPreference.<init>(DialogPreference.java:90)
Error AndroidRuntime 25851         at android.preference.MultiSelectListPreference.<init>

also Cleanup whitespace :/

Change-Id: I3f0a1fba8f6651522e4f0c4e4750b2ce0042314f