[ntuple] Remove unused RFieldDescriptorBuilder constructor

Author: hahnjo

tree/ntuple/inc/ROOT/RNTupleDescriptor.hxx

@@ -1319,14 +1319,6 @@ private:
 public:
    /// Make an empty dangling field descriptor.
    RFieldDescriptorBuilder() = default;
-   /// Make a new RFieldDescriptorBuilder based off an existing descriptor.
-   /// Relationship information is lost during the conversion to a
-   /// dangling descriptor:
-   /// * Parent id is reset to an invalid id.
-   /// * Field children ids are forgotten.
-   ///
-   /// These properties must be set using RNTupleDescriptorBuilder::AddFieldLink().
-   explicit RFieldDescriptorBuilder(const RFieldDescriptor &fieldDesc);
 
    /// Make a new RFieldDescriptorBuilder based off a live RNTuple field.
    static RFieldDescriptorBuilder FromField(const ROOT::RFieldBase &field);

tree/ntuple/src/RNTupleDescriptor.cxx

@@ -1128,14 +1128,6 @@ ROOT::RResult<ROOT::RColumnDescriptor> ROOT::Internal::RColumnDescriptorBuilder:
    return fColumn.Clone();
 }
 
-ROOT::Internal::RFieldDescriptorBuilder::RFieldDescriptorBuilder(const RFieldDescriptor &fieldDesc)
-   : fField(fieldDesc.Clone())
-{
-   fField.fParentId = ROOT::kInvalidDescriptorId;
-   fField.fLinkIds = {};
-   fField.fLogicalColumnIds = {};
-}
-
 ROOT::Internal::RFieldDescriptorBuilder
 ROOT::Internal::RFieldDescriptorBuilder::FromField(const ROOT::RFieldBase &field)
 {