Add a flag for the VRR small dirty detection

Test: presubmit
Bug: 283055450
Change-Id: Iea2b2edc65e2b5d702f380c655c37327f0aa1308
diff --git a/services/surfaceflinger/surfaceflinger_flags.aconfig b/services/surfaceflinger/surfaceflinger_flags.aconfig
index d4ab786..fedf08b 100644
--- a/services/surfaceflinger/surfaceflinger_flags.aconfig
+++ b/services/surfaceflinger/surfaceflinger_flags.aconfig
@@ -30,3 +30,11 @@
   bug: "284845445"
   is_fixed_read_only: true
 }
+
+flag {
+  name: "vrr_small_dirty_detection"
+  namespace: "core_graphics"
+  description: "Controls small dirty detection for VRR"
+  bug: "283055450"
+  is_fixed_read_only: true
+}