Soong AAR prebuilt support

Add support for android_library_import modules that take an
aar file.

Bug: 73724997
Test: m checkbuild
Change-Id: I670b56f0a3b7501d9478a6064a04d0cb9c1bb611
diff --git a/Android.bp b/Android.bp
index f2bc5fb..1d2c516 100644
--- a/Android.bp
+++ b/Android.bp
@@ -215,6 +215,7 @@
     ],
     srcs: [
         "java/aapt2.go",
+        "java/aar.go",
         "java/androidmk.go",
         "java/app_builder.go",
         "java/app.go",