add flag for CS aduio flicker

b/290847206 was merged to V without a flag to gate the new logic.
This CL gates all the changes in b/290847206 and updates 2 tests.

Fixes: 309540769
Bug: 290847206 (original bug)
Test: updated 2 unit tests
Change-Id: I05dfa70e06154f3f8a114455432e04b0e77b3a56
diff --git a/flags/Android.bp b/flags/Android.bp
index 7e2b31d..4f43a52 100644
--- a/flags/Android.bp
+++ b/flags/Android.bp
@@ -29,10 +29,11 @@
       "telecom_incallservice_flags.aconfig",
       "telecom_default_phone_account_flags.aconfig",
       "telecom_callaudioroutestatemachine_flags.aconfig",
+      "telecom_calls_manager_flags.aconfig",
       "telecom_anomaly_report_flags.aconfig",
       "telecom_callaudiomodestatemachine_flags.aconfig",
       "telecom_calllog_flags.aconfig",
-      "telecom_resolve_hidden_dependencies.aconfig"
+      "telecom_resolve_hidden_dependencies.aconfig",
     ],
 }