Import tokio-test v0.4.0

Bug: 179649848
Test: atest
Change-Id: I5e69ddc88c6f8d6d8a54927eb21736c9589d0f68
diff --git a/TEST_MAPPING b/TEST_MAPPING
new file mode 100644
index 0000000..f89e407
--- /dev/null
+++ b/TEST_MAPPING
@@ -0,0 +1,17 @@
+// Generated by update_crate_tests.py for tests that depend on this crate.
+{
+  "presubmit": [
+    {
+      "name": "tokio-test_device_test_tests_io"
+    },
+    {
+      "name": "tokio-test_device_test_src_lib"
+    },
+    {
+      "name": "tokio-test_device_test_tests_block_on"
+    },
+    {
+      "name": "tokio-test_device_test_tests_macros"
+    }
+  ]
+}