Migrate NEW_AOD_TRANSITION to aconfig

Test: NONE
Bug: b/301915812
Flag: ACONFIG com.android.systemui.Flags.FLAG_NEW_AOD_TRANSITION DEVELOPMENT
Change-Id: Ib95b8df30e91b22e5d681ccf79b65818e697157a
diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index e340209..d0b471a 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -119,4 +119,11 @@
     description: "Adds thread-local data to System UI's global coroutine scopes to "
         "allow for tracing of coroutine continuations using System UI's tracinglib"
     bug: "289353932"
+}
+
+flag {
+    name: "new_aod_transition"
+    namespace: "systemui"
+    description: "New LOCKSCREEN <=> AOD transition"
+    bug: "301915812"
 }
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