Clean DecoderLayerStack, similar to EncoderLayerStack.
(self,
name,
sub_layers,
num=1,
conv_kernel_size=None,
norm_type='ln',
norm_policy='pre',
use_repeat_layer=False,
spmd_pipeline_stages=1,
spmd_pipeline_microbatches=None,
start_layer_id=0,
has_final_layer=True)
source not stored for this graph (policy: none)