Use SettingsLib's versions of Custom* classes.

Test: make RunSettingsRoboTests
Change-Id: I2584e820b72bb4672c53fd1a9f63c7f1662e0809
diff --git a/src/com/android/settings/SeekBarDialogPreference.java b/src/com/android/settings/SeekBarDialogPreference.java
index a40df55..507c551 100644
--- a/src/com/android/settings/SeekBarDialogPreference.java
+++ b/src/com/android/settings/SeekBarDialogPreference.java
@@ -23,6 +23,8 @@
 import android.widget.ImageView;
 import android.widget.SeekBar;
 
+import com.android.settingslib.CustomDialogPreference;
+
 /**
  * Based on frameworks/base/core/java/android/preference/SeekBarDialogPreference.java
  * except uses support lib preferences.