Freeze DnsResolver AIDL API as v4.

It needs to be frozen because unstable version in REL will be
disallowed.

Bug: 133526962
Bug: 151074535
Test: m
Merged-In: I5cbae9a5039c88bf111bacf18f3c01a2cf72ed75
Change-Id: I9ccadadd559c352a6c33bb40c419b1cee65f5f9b
(cherry picked from commit 51d716ff1b57b4a04e487aa66a97f0246b933f45)
diff --git a/Android.bp b/Android.bp
index 3abd328..c137eed 100644
--- a/Android.bp
+++ b/Android.bp
@@ -37,6 +37,7 @@
         "1",
         "2",
         "3",
+        "4",
     ],
 }
 
@@ -217,11 +218,18 @@
 // TODO: Move this test to tests/
 cc_test {
     name: "resolv_unit_test",
-    test_suites: ["device-tests", "mts"],
+    test_suites: [
+        "device-tests",
+        "mts",
+    ],
     require_root: true,
     // TODO: Drop root privileges and make it be an real unit test.
     // TODO: Remove resolv_test_mts_coverage_defaults after mts coverage switched to 64-bit device.
-    defaults: ["netd_defaults", "resolv_test_defaults", "resolv_test_mts_coverage_defaults"],
+    defaults: [
+        "netd_defaults",
+        "resolv_test_defaults",
+        "resolv_test_mts_coverage_defaults",
+    ],
     srcs: [
         "resolv_cache_unit_test.cpp",
         "resolv_callback_unit_test.cpp",