New time zone picker page

- Show current selected region and time zone in a 2 rows.
  Defailed info of current selected time zone in footer
- Show option menu to switch to select UTC offset
- This picker will be changed to the default picker in a later CL

Bug: 73952488
Test: m RunSettingsRoboTests
Change-Id: Ia81bb022e1021369612f5bd60c2c1f4d08db2af8
(cherry picked from commit b7d588f341)

src/com/android/settings/datetime/timezone/FixedOffsetPreferenceController.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2018 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.timezone;
+
+import android.content.Context;
+import android.support.v7.preference.Preference;
+
+public class FixedOffsetPreferenceController extends BaseTimeZonePreferenceController {
+
+    private static final String PREFERENCE_KEY = "fixed_offset";
+
+    private TimeZoneInfo mTimeZoneInfo;
+
+    public FixedOffsetPreferenceController(Context context) {
+        super(context, PREFERENCE_KEY);
+    }
+
+    @Override
+    public CharSequence getSummary() {
+        // This is a Spannable object, which contains TTS span. It shouldn't be converted to String.
+        return mTimeZoneInfo == null ? "" : mTimeZoneInfo.getGmtOffset();
+    }
+
+    public void setTimeZoneInfo(TimeZoneInfo timeZoneInfo) {
+        mTimeZoneInfo = timeZoneInfo;
+    }
+
+    public TimeZoneInfo getTimeZoneInfo() {
+        return mTimeZoneInfo;
+    }
+}
+