Migrate framework-connectivity internal resources

Use ServiceConnectivityResources instead.
Start by creating resources in the ServiceConnectivityResources package
to match the internal configuration, and common overlays.

Bug: 182125649
Test: device boots, has connectivity
Change-Id: I77a3efca2cd644f9828db1ed5d3cae8070fb8363
Merged-In: I77a3efca2cd644f9828db1ed5d3cae8070fb8363
diff --git a/framework/src/android/net/ConnectivityResources.java b/framework/src/android/net/ConnectivityResources.java
new file mode 100644
index 0000000..18f0de0
--- /dev/null
+++ b/framework/src/android/net/ConnectivityResources.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2021 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.net;
+
+import static android.content.pm.PackageManager.MATCH_SYSTEM_ONLY;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.content.res.Resources;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.util.List;
+
+/**
+ * Utility to obtain the {@link com.android.server.ConnectivityService} {@link Resources}, in the
+ * ServiceConnectivityResources APK.
+ * @hide
+ */
+public class ConnectivityResources {
+    private static final String RESOURCES_APK_INTENT =
+            "com.android.server.connectivity.intent.action.SERVICE_CONNECTIVITY_RESOURCES_APK";
+    private static final String RES_PKG_DIR = "/apex/com.android.tethering/";
+
+    @NonNull
+    private final Context mContext;
+
+    @Nullable
+    private Context mResourcesContext = null;
+
+    @Nullable
+    private static Context sTestResourcesContext = null;
+
+    public ConnectivityResources(Context context) {
+        mContext = context;
+    }
+
+    /**
+     * Convenience method to mock all resources for the duration of a test.
+     *
+     * Call with a null context to reset after the test.
+     */
+    @VisibleForTesting
+    public static void setResourcesContextForTest(@Nullable Context testContext) {
+        sTestResourcesContext = testContext;
+    }
+
+    /**
+     * Get the {@link Context} of the resources package.
+     */
+    public synchronized Context getResourcesContext() {
+        if (sTestResourcesContext != null) {
+            return sTestResourcesContext;
+        }
+
+        if (mResourcesContext != null) {
+            return mResourcesContext;
+        }
+
+        final List<ResolveInfo> pkgs = mContext.getPackageManager()
+                .queryIntentActivities(new Intent(RESOURCES_APK_INTENT), MATCH_SYSTEM_ONLY);
+        pkgs.removeIf(pkg -> !pkg.activityInfo.applicationInfo.sourceDir.startsWith(RES_PKG_DIR));
+        if (pkgs.size() > 1) {
+            Log.wtf(ConnectivityResources.class.getSimpleName(),
+                    "More than one package found: " + pkgs);
+        }
+        if (pkgs.isEmpty()) {
+            throw new IllegalStateException("No connectivity resource package found");
+        }
+
+        final Context pkgContext;
+        try {
+            pkgContext = mContext.createPackageContext(
+                    pkgs.get(0).activityInfo.applicationInfo.packageName, 0 /* flags */);
+        } catch (PackageManager.NameNotFoundException e) {
+            throw new IllegalStateException("Resolved package not found", e);
+        }
+
+        mResourcesContext = pkgContext;
+        return pkgContext;
+    }
+
+    /**
+     * Get the {@link Resources} of the ServiceConnectivityResources APK.
+     */
+    public Resources get() {
+        return getResourcesContext().getResources();
+    }
+}