Add rust_test and update TEST_MAPPING

Test: atest -c --include-subdirs external/rust/crates
Change-Id: I5fff17757326aa70ce7c9a672a2362abd8ed26d5
diff --git a/Android.bp b/Android.bp
index 82efe98..27ab02d 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,4 +1,4 @@
-// This file is generated by cargo2android.py --run --device --dependencies.
+// This file is generated by cargo2android.py --run --device --dependencies --tests.
 
 rust_library {
     name: "libproc_macro_nested",
@@ -7,3 +7,22 @@
     srcs: ["src/lib.rs"],
     edition: "2015",
 }
+
+rust_defaults {
+    name: "proc-macro-nested_defaults",
+    crate_name: "proc_macro_nested",
+    srcs: ["src/lib.rs"],
+    test_suites: ["general-tests"],
+    auto_gen_config: true,
+    edition: "2015",
+}
+
+rust_test_host {
+    name: "proc-macro-nested_host_test_src_lib",
+    defaults: ["proc-macro-nested_defaults"],
+}
+
+rust_test {
+    name: "proc-macro-nested_device_test_src_lib",
+    defaults: ["proc-macro-nested_defaults"],
+}