A key describing the temporal layering schema. This is an optional parameter that applies only to video encoders. Use MediaCodec.InputFormat after MediaCodec.Configure(MediaFormat, Android.Views.Surface, Android.Views.Surface, Android.Views.Surface) to query if the encoder supports the desired schema. Supported values are webrtc.vp8.1-layer, webrtc.vp8.2-layer, webrtc.vp8.3-layer, and none. If the encoder does not support temporal layering, the input format will not have an entry with this key. The associated value is a string.