Sets or clears Geolocation permissions for Google origins when the 'Location & privacy - Share with Google' sysetm setting is changed.

This fixes bug http://b/issue?id=1933893

core/java/android/GoogleLocationSettingManager.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2009 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 android.webkit;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.content.SharedPreferences.Editor;
+import android.database.ContentObserver;
+import android.os.Handler;
+import android.preference.PreferenceManager;
+import android.provider.Settings;
+
+import java.util.HashSet;
+
+/**
+ * A class to manage the interaction between the system setting 'Location &
+ * Security - Share with Google' and the browser. When this setting is set
+ * to true, we allow Geolocation for Google origins. When this setting is
+ * set to false, we clear Geolocation permissions for Google origins.
+ * @hide pending API council review
+ */
+class GoogleLocationSettingManager {
+    // The application context.
+    private Context mContext;
+    // The observer used to listen to the system setting.
+    private GoogleLocationSettingObserver mSettingObserver;
+
+    // The value of the system setting that indicates true.
+    private final static int sSystemSettingTrue = 1;
+    // The value of the system setting that indicates false.
+    private final static int sSystemSettingFalse = 0;
+    // The value of the USE_LOCATION_FOR_SERVICES system setting last read
+    // by the browser.
+    private final static String LAST_READ_USE_LOCATION_FOR_SERVICES =
+            "lastReadUseLocationForServices";
+    // The Google origins we consider.
+    private static HashSet<String> sGoogleOrigins;
+    static {
+        sGoogleOrigins = new HashSet<String>();
+        // NOTE: DO NOT ADD A "/" AT THE END!
+        sGoogleOrigins.add("http://www.google.com");
+        sGoogleOrigins.add("http://www.google.co.uk");
+    }
+
+    GoogleLocationSettingManager(Context context) {
+        mContext = context;
+    }
+
+    /**
+     * Starts the manager. Checks whether the setting has changed and
+     * installs an observer to listen for future changes.
+     */
+    public void start() {
+        maybeApplySetting();
+
+        mSettingObserver = new GoogleLocationSettingObserver();
+        mSettingObserver.observe();
+    }
+
+    /**
+     * Checks to see if the system setting has changed and if so,
+     * updates the Geolocation permissions accordingly.
+     */
+    private void maybeApplySetting() {
+        int setting = getSystemSetting();
+        if (settingChanged(setting)) {
+            applySetting(setting);
+        }
+    }
+
+    /**
+     * Gets the current system setting for 'Use location for Google services'.
+     * @return The system setting.
+     */
+    private int getSystemSetting() {
+        return Settings.Secure.getInt(mContext.getContentResolver(),
+                                      Settings.Secure.USE_LOCATION_FOR_SERVICES,
+                                      sSystemSettingFalse);
+    }
+
+    /**
+     * Determines whether the supplied setting has changed from the last
+     * value read by the browser.
+     * @param setting The setting.
+     * @return Whether the setting has changed from the last value read
+     *     by the browser.
+     */
+    private boolean settingChanged(int setting) {
+        SharedPreferences preferences =
+                PreferenceManager.getDefaultSharedPreferences(mContext);
+        // Default to false. If the system setting is false the first time it is ever read by the
+        // browser, there's nothing to do.
+        int lastReadSetting = sSystemSettingFalse;
+        lastReadSetting = preferences.getInt(LAST_READ_USE_LOCATION_FOR_SERVICES,
+                                             lastReadSetting);
+
+        if (lastReadSetting == setting) {
+            return false;
+        }
+
+        Editor editor = preferences.edit();
+        editor.putInt(LAST_READ_USE_LOCATION_FOR_SERVICES, setting);
+        editor.commit();
+        return true;
+    }
+
+    /**
+     * Applies the supplied setting to the Geolocation permissions.
+     * @param setting The setting.
+     */
+    private void applySetting(int setting) {
+        for (String origin : sGoogleOrigins) {
+            if (setting == sSystemSettingTrue) {
+                GeolocationPermissions.getInstance().allow(origin);
+            } else {
+                GeolocationPermissions.getInstance().clear(origin);
+            }
+        }
+    }
+
+    /**
+     * This class implements an observer to listen for changes to the
+     * system setting.
+     */
+    class GoogleLocationSettingObserver extends ContentObserver {
+        GoogleLocationSettingObserver() {
+            super(new Handler());
+        }
+
+        void observe() {
+            ContentResolver resolver = mContext.getContentResolver();
+            resolver.registerContentObserver(Settings.Secure.getUriFor(
+                Settings.Secure.USE_LOCATION_FOR_SERVICES), false, this);
+        }
+
+        @Override
+        public void onChange(boolean selfChange) {
+            maybeApplySetting();
+        }
+    }
+}