Introduce aconfig flag to report anamaly for config changed

Bug: 270757342
Test: atest FrameworksTelephonyTestCases
Change-Id: Ic7a86daf3b328f84b52878ff097711b5d05c3402
diff --git a/flags/misc.aconfig b/flags/misc.aconfig
index e67dabe..aabceca 100644
--- a/flags/misc.aconfig
+++ b/flags/misc.aconfig
@@ -80,3 +80,13 @@
         purpose: PURPOSE_BUGFIX
     }
 }
+
+flag {
+    name: "add_anomaly_when_notify_config_changed_with_invalid_phone"
+    namespace: "telephony"
+    description: "Report anomaly when CarrierConfigLoader received config change with sub that maps to invalid phoneId"
+    bug:"270757342"
+    metadata {
+        purpose: PURPOSE_BUGFIX
+    }
+}