Add bugfix flag for bg icon updates for media notif

Bug: 315143160
Test: builds
Flag: ACONFIG com.android.systemui.notifications_background_media_icons DISABLED
Change-Id: Ifa7cd2b3604a7b5b1d09eaa77a093877babea270
diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index ba3026e..5197556 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -67,6 +67,16 @@
 }
 
 flag {
+    name: "notifications_background_media_icons"
+    namespace: "systemui"
+    description: "Updates icons for media notifications in the background."
+    bug: "315143160"
+    metadata {
+        purpose: PURPOSE_BUGFIX
+    }
+}
+
+flag {
     name: "nssl_falsing_fix"
     namespace: "systemui"
     description: "Minor touch changes to prevent falsing errors in NSSL"