Remove precision_plugin pre_dispatch() method (#10887)

* Remove precision_plugin pre_dispatch() method

* update changelog

CHANGELOG.md

@@ -188,6 +188,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Removed argument `return_result` from the `DDPSpawnPlugin.spawn()` method ([#10867](https://github.com/PyTorchLightning/pytorch-lightning/pull/10867))
 
 
+- Removed method `pre_dispatch` from the `PrecisionPlugin` method ([#10887](https://github.com/PyTorchLightning/pytorch-lightning/pull/10887))
+
+
 ### Fixed
 
 - Fixed an issue with `SignalConnector` not restoring the default signal handlers on teardown when running on SLURM or with fault-tolerant training enabled ([#10611](https://github.com/PyTorchLightning/pytorch-lightning/pull/10611))

pytorch_lightning/accelerators/accelerator.py

@@ -79,8 +79,6 @@ class Accelerator:
         if self.training_type_plugin.setup_optimizers_in_pre_dispatch:
             self.training_type_plugin.setup_optimizers(trainer)
 
-        self.training_type_plugin.precision_plugin.pre_dispatch()
-
     def dispatch(self, trainer: "pl.Trainer") -> None:
         """Hook to do something before the training/evaluation/prediction starts."""
         self.training_type_plugin.dispatch(trainer)

pytorch_lightning/plugins/precision/precision_plugin.py

@@ -201,9 +201,6 @@ class PrecisionPlugin(CheckpointHooks):
         parameters = self.main_params(optimizer)
         torch.nn.utils.clip_grad_norm_(parameters, clip_val)
 
-    def pre_dispatch(self) -> None:
-        """Hook to do something before the training/evaluation/prediction starts."""
-
     def dispatch(self, trainer: "pl.Trainer") -> None:
         """Hook to do something when ``Accelerator.dispatch()`` gets called."""