アセット全体が強制的に含まれます。
For example if you pass a Mesh into the BuildPipeline.BuildAssetBundle function and use CompleteAssets it would also include
the game object and any animation clips in the same asset.
This flag is only taken into account when calling the obsolete BuildPipeline.BuildAssetBundle method. When calling BuildPipeline.BuildAssetBundles this behaviour is always disabled.