Updates app to use latest pin lock library.

[roundhill]

Fixes #289

[beaucollins]

This introduces an NPE crash when switching themes in PreferencesActivity:

E/AndroidRuntime( 1981): java.lang.RuntimeException: Unable to stop activity {com.android.quicksearchbox/com.android.quicksearchbox.SearchActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'com.android.quicksearchbox.SourceResult com.android.quicksearchbox.Suggestions.getResult()' on a null object reference
E/AndroidRuntime( 1981):    at android.app.ActivityThread.performStopActivityInner(ActivityThread.java:3382)
E/AndroidRuntime( 1981):    at android.app.ActivityThread.handleStopActivity(ActivityThread.java:3428)
E/AndroidRuntime( 1981):    at android.app.ActivityThread.access$1100(ActivityThread.java:151)
E/AndroidRuntime( 1981):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1332)
E/AndroidRuntime( 1981):    at android.os.Handler.dispatchMessage(Handler.java:102)
E/AndroidRuntime( 1981):    at android.os.Looper.loop(Looper.java:135)
E/AndroidRuntime( 1981):    at android.app.ActivityThread.main(ActivityThread.java:5257)
E/AndroidRuntime( 1981):    at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime( 1981):    at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime( 1981):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
E/AndroidRuntime( 1981):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
E/AndroidRuntime( 1981): Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.android.quicksearchbox.SourceResult com.android.quicksearchbox.Suggestions.getResult()' on a null object reference
E/AndroidRuntime( 1981):    at com.android.quicksearchbox.SearchActivity.getCurrentSuggestions(SearchActivity.java:370)
E/AndroidRuntime( 1981):    at com.android.quicksearchbox.SearchActivity.onStop(SearchActivity.java:267)
E/AndroidRuntime( 1981):    at android.app.Instrumentation.callActivityOnStop(Instrumentation.java:1277)
E/AndroidRuntime( 1981):    at android.app.Activity.performStop(Activity.java:6142)
E/AndroidRuntime( 1981):    at android.app.ActivityThread.performStopActivityInner(ActivityThread.java:3379)
E/AndroidRuntime( 1981):    ... 10 more

[roundhill]

This introduces an NPE crash when switching themes in PreferencesActivity:

Thanks @beaucollins! I fixed that. Ready for another look.