Refactor time format preference to be more modular/testable

Change-Id: Ib6c06de9f942c3bb06384947f6b1923b33e511bc
Fixes: 32972964
Test: make RunSettingsRoboTests
diff --git a/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java b/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java
new file mode 100644
index 0000000..e89b5da
--- /dev/null
+++ b/src/com/android/settings/datetime/UpdateTimeAndDateCallback.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.datetime;
+
+import android.content.Context;
+
+public interface UpdateTimeAndDateCallback {
+
+    void updateTimeAndDateDisplay(Context context);
+}