Pass config files to metalava

Adds a filegroup "metalava-config-files" whose contents are passed to
Metalava using the `--config-file` option.

Bug: 354699349
Test: m checkapi
Change-Id: I1e246517c2ef678e41214c975aecee97f9faca67
diff --git a/java/metalava/source-model-selection-config.xml b/java/metalava/source-model-selection-config.xml
new file mode 100644
index 0000000..c61196f
--- /dev/null
+++ b/java/metalava/source-model-selection-config.xml
@@ -0,0 +1,19 @@
+<!--
+  ~ Copyright (C) 2024 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.
+  -->
+
+<config xmlns="http://www.google.com/tools/metalava/config"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://www.google.com/tools/metalava/config ../../../../tools/metalava/metalava/src/main/resources/schemas/config.xsd"/>