Formalize Connection CallQuality report APIs

Promote Connection#EVENT_CALL_QUALITY_REPORT as well as
Connection#EXTRA_CALL_QUALITY_REPORT into proper system APIs. These are
used by Telephony to send the call quality report from Telephony over to
Telecom which is retreived by CallDiagnosticService.

Bug: 322513691
Bug: 311773409
Test: atest CtsCallDiagnosticService
Change-Id: I06c0cd021d1de3ff54ead59fb7483547599193e3
diff --git a/telecomm/java/android/telecom/Connection.java b/telecomm/java/android/telecom/Connection.java
index a2105b0..c3b9ed4 100644
--- a/telecomm/java/android/telecom/Connection.java
+++ b/telecomm/java/android/telecom/Connection.java
@@ -21,6 +21,7 @@
 import android.Manifest;
 import android.annotation.CallbackExecutor;
 import android.annotation.ElapsedRealtimeLong;
+import android.annotation.FlaggedApi;
 import android.annotation.IntDef;
 import android.annotation.IntRange;
 import android.annotation.NonNull;
@@ -56,6 +57,7 @@
 import com.android.internal.os.SomeArgs;
 import com.android.internal.telecom.IVideoCallback;
 import com.android.internal.telecom.IVideoProvider;
+import com.android.server.telecom.flags.Flags;
 
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
@@ -1015,9 +1017,11 @@
     /**
      * Connection event used to communicate a {@link android.telephony.CallQuality} report from
      * telephony to Telecom for relaying to
-     * {@link DiagnosticCall#onCallQualityReceived(CallQuality)}.
+     * {@link CallDiagnostics#onCallQualityReceived(CallQuality)}.
      * @hide
      */
+    @SystemApi
+    @FlaggedApi(Flags.FLAG_TELECOM_RESOLVE_HIDDEN_DEPENDENCIES)
     public static final String EVENT_CALL_QUALITY_REPORT =
             "android.telecom.event.CALL_QUALITY_REPORT";
 
@@ -1026,6 +1030,8 @@
      * {@link android.telephony.CallQuality} data.
      * @hide
      */
+    @SystemApi
+    @FlaggedApi(Flags.FLAG_TELECOM_RESOLVE_HIDDEN_DEPENDENCIES)
     public static final String EXTRA_CALL_QUALITY_REPORT =
             "android.telecom.extra.CALL_QUALITY_REPORT";