add a flag for ConnectionServiceFocusManager#getCurrentFocusCall

A flag should have been added with the changes in b/280128990.  Gating the changed code with a flag to ensure the code has enough soak time before release.

Fixes: 309541253
Bug:  280128990 (original bug)
Test: build + existing tests
Change-Id: Ibb19b05f5005e885fe5dde690f74ad37f7d062d7
diff --git a/flags/Android.bp b/flags/Android.bp
index 450cb1b..7e2b31d 100644
--- a/flags/Android.bp
+++ b/flags/Android.bp
@@ -29,6 +29,7 @@
       "telecom_incallservice_flags.aconfig",
       "telecom_default_phone_account_flags.aconfig",
       "telecom_callaudioroutestatemachine_flags.aconfig",
+      "telecom_anomaly_report_flags.aconfig",
       "telecom_callaudiomodestatemachine_flags.aconfig",
       "telecom_calllog_flags.aconfig",
       "telecom_resolve_hidden_dependencies.aconfig"