Don't enable speakerphone when video enabled if headset on

Fixes #6431
// FREEBIE

src/org/thoughtcrime/securesms/service/WebRtcCallService.java

@@ -748,7 +748,11 @@ public class WebRtcCallService extends Service implements InjectableType, PeerCo
       else                   this.lockManager.updatePhoneState(LockManager.PhoneState.IN_CALL);
     }
 
-    if (localVideoEnabled && !audioManager.isSpeakerphoneOn() && !audioManager.isBluetoothScoOn()) {
+    if (localVideoEnabled &&
+        !audioManager.isSpeakerphoneOn() &&
+        !audioManager.isBluetoothScoOn() &&
+        !audioManager.isWiredHeadsetOn())
+    {
       audioManager.setSpeakerphoneOn(true);
     }