Add new system service CountryDetector

a. The CountryDetector detects the country the user is in
   in order of mobile network, location, sim card or locale.
   It will be used by contact and contact provider.

b. All added APIs are hidden at this stage.

Change-Id: I4ba278571ffb6ab6ded0996d4f440a18534f8ed4
diff --git a/services/java/com/android/server/location/CountryDetectorBase.java b/services/java/com/android/server/location/CountryDetectorBase.java
new file mode 100644
index 0000000..8326ef9
--- /dev/null
+++ b/services/java/com/android/server/location/CountryDetectorBase.java
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2010 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.server.location;
+
+import android.content.Context;
+import android.location.Country;
+import android.location.CountryListener;
+import android.os.Handler;
+
+/**
+ * This class defines the methods need to be implemented by the country
+ * detector.
+ * <p>
+ * Calling {@link #detectCountry} to start detecting the country. The country
+ * could be returned immediately if it is available.
+ *
+ * @hide
+ */
+public abstract class CountryDetectorBase {
+    protected final Handler mHandler;
+    protected final Context mContext;
+    protected CountryListener mListener;
+    protected Country mDetectedCountry;
+
+    public CountryDetectorBase(Context ctx) {
+        mContext = ctx;
+        mHandler = new Handler();
+    }
+
+    /**
+     * Start detecting the country that the user is in.
+     *
+     * @return the country if it is available immediately, otherwise null should
+     *         be returned.
+     */
+    public abstract Country detectCountry();
+
+    /**
+     * Register a listener to receive the notification when the country is detected or changed.
+     * <p>
+     * The previous listener will be replaced if it exists.
+     */
+    public void setCountryListener(CountryListener listener) {
+        mListener = listener;
+    }
+
+    /**
+     * Stop detecting the country. The detector should release all system services and be ready to
+     * be freed
+     */
+    public abstract void stop();
+
+    protected void notifyListener(Country country) {
+        if (mListener != null) {
+            mListener.onCountryDetected(country);
+        }
+    }
+}