Mega community pipeline (#1561)

* Mega community pipeline

* fix

examples/community/stable_diffusion_mega.py

@@ -50,6 +50,7 @@ class StableDiffusionMegaPipeline(DiffusionPipeline):
         feature_extractor ([`CLIPFeatureExtractor`]):
             Model that extracts features from generated images to be used as inputs for the `safety_checker`.
     """
+    _optional_components = ["safety_checker", "feature_extractor"]
 
     def __init__(
         self,
@@ -60,6 +61,7 @@ def __init__(
         scheduler: Union[DDIMScheduler, PNDMScheduler, LMSDiscreteScheduler],
         safety_checker: StableDiffusionSafetyChecker,
         feature_extractor: CLIPFeatureExtractor,
+        requires_safety_checker: bool = True,
     ):
         super().__init__()
         if hasattr(scheduler.config, "steps_offset") and scheduler.config.steps_offset != 1:
@@ -85,6 +87,7 @@ def __init__(
             safety_checker=safety_checker,
             feature_extractor=feature_extractor,
         )
+        self.register_to_config(requires_safety_checker=requires_safety_checker)
 
     @property
     def components(self) -> Dict[str, Any]: