[FKeyPropertyResult](API\Editor\Sequencer\FKeyPropertyResult) AddAttachedMediaSource ( [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) KeyTime, class [UMediaSource](API\Runtime\MediaAssets\UMediaSource) * MediaSource, [TArray](API\Runtime\Core\Containers\TArray)< [TWeakObjectPtr](API\Runtime\Core\UObject\TWeakObjectPtr)< [UObject](API\Runtime\CoreUObject\UObject\UObject) >> ObjectsToAttachTo, int32 RowIndex )