BucketHeadP65

Federated DPFTRL and Adaptive Clipping noise injection.

1

Dear developers of the privacy framework. I was checking the implementation of [quantile_adaptive_clip_tree_query.py](https://github.com/tensorflow/privacy/blob/master/tensorflow_privacy/privacy/dp_query/quantile_adaptive_clip_tree_query.py) I can see that a new tree is required to inject noise after aggregating the norm bit...