Create the TEST_MAPPING file

Add FlagAnnotationTests in presubmit to ensure that test filtering rule
always works as expected.

Test: atest --test-mapping
Bug: 277819423
Change-Id: I7cc3a70495f8d62ed7a5b26edc4fd240e73ccf61

tools/aconfig/TEST_MAPPING

@@ -0,0 +1,15 @@
+{
+  "presubmit": [
+    {
+      // Ensure changes on aconfig auto generated library is compatible with
+      // test testing filtering logic. Breakage on this test means all tests
+      // that using the flag annotations to do filtering will get affected.
+      "name": "FlagAnnotationTests",
+      "options": [
+        {
+          "include-filter": "android.cts.flags.tests.FlagAnnotationTest"
+        }
+      ]
+    }
+  ]
+}