Add rust_test and update TEST_MAPPING

Test: atest -c --include-subdirs external/rust/crates
Change-Id: I7b5dace931c81514ec1f67007cddfe49e03e485f
diff --git a/Android.bp b/Android.bp
index b65ed9d..ad3f7e8 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,4 +1,4 @@
-// This file is generated by cargo2android.py --run --dependencies.
+// This file is generated by cargo2android.py --run --dependencies --tests.
 
 rust_proc_macro {
     name: "libpaste_impl",
@@ -10,5 +10,17 @@
     ],
 }
 
+rust_test_host {
+    name: "paste-impl_host_test_src_lib",
+    crate_name: "paste_impl",
+    srcs: ["src/lib.rs"],
+    test_suites: ["general-tests"],
+    auto_gen_config: true,
+    edition: "2018",
+    proc_macros: [
+        "libproc_macro_hack",
+    ],
+}
+
 // dependent_library ["feature_list"]
 //   proc-macro-hack-0.5.16
diff --git a/TEST_MAPPING b/TEST_MAPPING
new file mode 100644
index 0000000..c791286
--- /dev/null
+++ b/TEST_MAPPING
@@ -0,0 +1,9 @@
+// Generated by cargo2android.py for tests in Android.bp
+{
+  "presubmit": [
+    {
+      "name": "paste-impl_host_test_src_lib",
+      "host": true
+    }
+  ]
+}