monkey caused a total system restart

gistfile1.txt

```
:Sending Touch (ACTION_UP): 0:(671.28577,1415.2507)
// CRASH: null (pid 2587)
// Short Msg: java.util.ConcurrentModificationException
// Long Msg: java.util.ConcurrentModificationException
// Build Label: google/sdk_gphone_x86/generic_x86:8.0.0/OSR1.170901.056/4497355:userdebug/dev-keys
// Build Changelist: 4497355
// Build Time: 1513035881000
// java.util.ConcurrentModificationException
// 	at java.util.ArrayList.forEach(ArrayList.java:1268)
// 	at com.android.server.TextServicesManagerService$SpellCheckerBindGroup.onServiceConnected(TextServicesManagerService.java:863)
// 	at com.android.server.TextServicesManagerService$InternalServiceConnection.onServiceConnectedInnerLocked(TextServicesManagerService.java:1015)
// 	at com.android.server.TextServicesManagerService$InternalServiceConnection.onServiceConnected(TextServicesManagerService.java:1003)
// 	at android.app.LoadedApk$ServiceDispatcher.doConnected(LoadedApk.java:1634)
// 	at android.app.LoadedApk$ServiceDispatcher$RunConnection.run(LoadedApk.java:1663)
// 	at android.os.Handler.handleCallback(Handler.java:789)
// 	at android.os.Handler.dispatchMessage(Handler.java:98)
// 	at android.os.Looper.loop(Looper.java:164)
// 	at com.android.server.SystemServer.run(SystemServer.java:421)
// 	at com.android.server.SystemServer.main(SystemServer.java:260)
// 	at java.lang.reflect.Method.invoke(Native Method)
// 	at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
// 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
// 
** Error: A RuntimeException occurred:
```