Organize incremental test plan for PackageManager

This patch adds libincfs-test and service.incremental_test in the
presubmit process.

Test: atest service.incremental_test
Test: atest libincfs-test
Test: atest -p system/incremental_delivery/incfs
    http://ab/I24700010005521991

Bug: 180650365
Change-Id: Iaea12556d398893875c4ab3bb928477103fa7c18
diff --git a/services/incremental/TEST_MAPPING b/services/incremental/TEST_MAPPING
index f2ad068..9fe090a 100644
--- a/services/incremental/TEST_MAPPING
+++ b/services/incremental/TEST_MAPPING
@@ -10,6 +10,12 @@
     },
     {
       "name": "CtsIncrementalInstallHostTestCases"
+    },
+    {
+      "name": "libincfs-test"
+    },
+    {
+      "name": "service.incremental_test"
     }
   ],
   "presubmit-large": [