pt 1 in reviving the android build (copied from pm 28a1, wish me luck)

mobile/android/base/java/org/mozilla/gecko/Locales.java

@@ -0,0 +1,136 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.lang.reflect.Method;
+import java.util.Locale;
+
+import org.mozilla.gecko.LocaleManager;
+
+import android.app.Activity;
+import android.content.Context;
+import android.os.Bundle;
+import android.os.StrictMode;
+import android.support.v4.app.FragmentActivity;
+import android.support.v7.app.AppCompatActivity;
+
+/**
+ * This is a helper class to do typical locale switching operations without
+ * hitting StrictMode errors or adding boilerplate to common activity
+ * subclasses.
+ *
+ * Either call {@link Locales#initializeLocale(Context)} in your
+ * <code>onCreate</code> method, or inherit from
+ * <code>LocaleAwareFragmentActivity</code> or <code>LocaleAwareActivity</code>.
+ */
+public class Locales {
+    public static LocaleManager getLocaleManager() {
+        try {
+            final Class<?> clazz = Class.forName("org.mozilla.gecko.BrowserLocaleManager");
+            final Method getInstance = clazz.getMethod("getInstance");
+            final LocaleManager localeManager = (LocaleManager) getInstance.invoke(null);
+            return localeManager;
+        } catch (Exception e) {
+          throw new RuntimeException(e);
+        }
+    }
+
+    public static void initializeLocale(Context context) {
+        final LocaleManager localeManager = getLocaleManager();
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+        StrictMode.allowThreadDiskWrites();
+        try {
+            localeManager.getAndApplyPersistedLocale(context);
+        } finally {
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+    }
+
+    public static abstract class LocaleAwareAppCompatActivity extends AppCompatActivity {
+        @Override
+        protected void onCreate(Bundle savedInstanceState) {
+            Locales.initializeLocale(getApplicationContext());
+            super.onCreate(savedInstanceState);
+        }
+
+    }
+    public static abstract class LocaleAwareFragmentActivity extends FragmentActivity {
+        @Override
+        protected void onCreate(Bundle savedInstanceState) {
+            Locales.initializeLocale(getApplicationContext());
+            super.onCreate(savedInstanceState);
+        }
+    }
+
+    public static abstract class LocaleAwareActivity extends Activity {
+        @Override
+        protected void onCreate(Bundle savedInstanceState) {
+            Locales.initializeLocale(getApplicationContext());
+            super.onCreate(savedInstanceState);
+        }
+    }
+
+    /**
+     * Sometimes we want just the language for a locale, not the entire language
+     * tag. But Java's .getLanguage method is wrong.
+     *
+     * This method is equivalent to the first part of
+     * {@link Locales#getLanguageTag(Locale)}.
+     *
+     * @return a language string, such as "he" for the Hebrew locales.
+     */
+    public static String getLanguage(final Locale locale) {
+        // Can, but should never be, an empty string.
+        final String language = locale.getLanguage();
+
+        // Modernize certain language codes.
+        if (language.equals("iw")) {
+            return "he";
+        }
+
+        if (language.equals("in")) {
+            return "id";
+        }
+
+        if (language.equals("ji")) {
+            return "yi";
+        }
+
+        return language;
+    }
+
+    /**
+     * Gecko uses locale codes like "es-ES", whereas a Java {@link Locale}
+     * stringifies as "es_ES".
+     *
+     * This method approximates the Java 7 method
+     * <code>Locale#toLanguageTag()</code>.
+     *
+     * @return a locale string suitable for passing to Gecko.
+     */
+    public static String getLanguageTag(final Locale locale) {
+        // If this were Java 7:
+        // return locale.toLanguageTag();
+
+        final String language = getLanguage(locale);
+        final String country = locale.getCountry(); // Can be an empty string.
+        if (country.equals("")) {
+            return language;
+        }
+        return language + "-" + country;
+    }
+
+    public static Locale parseLocaleCode(final String localeCode) {
+        int index;
+        if ((index = localeCode.indexOf('-')) != -1 ||
+            (index = localeCode.indexOf('_')) != -1) {
+            final String langCode = localeCode.substring(0, index);
+            final String countryCode = localeCode.substring(index + 1);
+            return new Locale(langCode, countryCode);
+        }
+
+        return new Locale(localeCode);
+    }
+}