Add a filegroup to allow exporting the kotlinx-coroutines-play-services src files

Bug: 228939367

Change-Id: I022a21232a683221267ce86dca62dde6dc0c2162
diff --git a/Android.bp b/Android.bp
index 0a3b2cf..5225d8c 100644
--- a/Android.bp
+++ b/Android.bp
@@ -141,3 +141,8 @@
         "//apex_available:anyapex"
     ],
 }
+
+filegroup {
+    name: "kotlinx-coroutines-play-services",
+    srcs: ["integration/kotlinx-coroutines-play-services/src/**/*.kt"],
+}