Add TEST_MAPPING for InputMethodStressTest.

Bug: 195468725
Test: atest --dry-run --test-mapping frameworks/base/tests/InputMethodStressTest:presubmit
Change-Id: I4cf126240f162cd45597ebcc232ccedb80abc745
diff --git a/tests/InputMethodStressTest/TEST_MAPPING b/tests/InputMethodStressTest/TEST_MAPPING
new file mode 100644
index 0000000..ad07205
--- /dev/null
+++ b/tests/InputMethodStressTest/TEST_MAPPING
@@ -0,0 +1,7 @@
+{
+  "presubmit": [
+    {
+      "name": "InputMethodStressTest"
+    }
+  ]
+}