Describe the bug

Onnxruntime defined some operators (like LayerNormalization, SimplifiedLayerNormalization etc) in onnx domain:

However, they are not standard onnx operators as listed in (https://github.com/onnx/onnx/blob/master/docs/Operators.md).

That causes some issue. For example, symbolic shape inference outputs warning:
Warning: Unsupported operator LayerNormalization. No schema registered for this operator.

Urgency
If there are particular important use cases blocked by this or strict project-related timelines, please share more information and dates. If there are no hard deadlines, please specify none.

None

System information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04):
• ONNX Runtime installed from (source or binary):
• ONNX Runtime version:
• Python version:
• Visual Studio version (if applicable):
• GCC/Compiler version (if compiling from source):
• CUDA/cuDNN version:
• GPU model and memory:

To Reproduce

• Describe steps/code to reproduce the behavior.
• Attach the ONNX model to the issue (where applicable) to expedite investigation.

Expected behavior
How about change to MS domain, and add some logic for backward compatible (like rewrite the domain for those operator during loading models).

Screenshots
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Additional context
Add any other context about the problem here. If the issue is about a particular model, please share the model details as well to facilitate debugging.