Update TEST_MAPPING am: 0ecaefed57

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/downcast-rs/+/1813715

Change-Id: I0aef8494570b347bb7fdd6db902383e99bc928d2
diff --git a/TEST_MAPPING b/TEST_MAPPING
new file mode 100644
index 0000000..25eb970
--- /dev/null
+++ b/TEST_MAPPING
@@ -0,0 +1,14 @@
+// Generated by update_crate_tests.py for tests that depend on this crate.
+{
+  "presubmit": [
+    {
+      "name": "downcast-rs_device_test_src_lib"
+    },
+    {
+      "name": "downcast-rs_device_test_tests_import_via_macro_use"
+    },
+    {
+      "name": "downcast-rs_device_test_tests_use_via_namespace"
+    }
+  ]
+}