Add force enabled backends array

* For easy use on adding default backends as overlay or rro

client/src/main/kotlin/org/microg/nlp/client/UnifiedLocationClient.kt

@@ -501,6 +501,8 @@ class UnifiedLocationClient private constructor(context: Context) {
             } catch (e: Exception) {
                 Log.w(TAG, "Failed to register location callback", e)
             }
+            context.get()?.resources?.getStringArray(R.array.force_location_backends)?.let { setLocationBackends(it + getLocationBackends()) }
+            context.get()?.resources?.getStringArray(R.array.force_geocoder_backends)?.let { setGeocoderBackends(it + getGeocoderBackends()) }
             updateServiceInterval()
             if (continuations.size > 0) {
                 Log.d(TAG, "Resuming ${continuations.size} continuations")

client/src/main/res/values/arrays.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2013-2020 microG Project Team
+  ~
+  ~ 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.
+  -->
+
+<resources>
+    <string-array name="force_location_backends" translatable="false">
+    </string-array>
+
+    <string-array name="force_geocoder_backends" translatable="false">
+    </string-array>
+</resources>