Filter out info from non-const initializers during shape inferencing (#1806)
* Don't return shape for non-const initializer in InferenceContextImpl::getInputType
Don't return initializer for non-const initializer in InferenceContextImpl::getInputData
Update graph_utils to support these scenarios
- fix GetConstantInitializer to make sure a name is for an outer scope value before checking a parent graph, as local name could shadow an outer scope initializer.