Bug in XsdDataContractImporter when importing ComplexType

[zabulus]

Description

We are currently in process of porting from .net4.8 to net7.0. Utility is used to customize generation of data contracts from .xsd files. Particular complex type in xsd is a dictionary of enum-key bool-value records.
Error message we encounter:

System.Runtime.Serialization.InvalidDataContractException: Array type 'ArrayOfKeyValueOfDayOfWeekbooleanRDHGY3MA' in namespace 'http://schemas.microsoft.com/2003/10/Serialization/Arrays' cannot be imported. It is an invalid dictionary type since element 'KeyValueOfDayOfWeekbooleanRDHGY3MA' references a type from a different namespace 'http://schemas.datacontract.org/2004/07/System.Runtime.Serialization'. Either fix the schema or remove the IsDictionary annotation. Either change the schema so that the types can map to data contract types or use ImportXmlType or use a different serializer.
   at System.Runtime.Serialization.SchemaImporter.ThrowTypeCannotBeImportedException(String message)
   at System.Runtime.Serialization.SchemaImporter.ImportCollection(XmlQualifiedName typeName, XmlSchemaSequence rootSequence, XmlSchemaObjectCollection attributes, XmlSchemaAnnotation annotation, Boolean isReference)
   at System.Runtime.Serialization.SchemaImporter.ImportType(XmlQualifiedName typeName, XmlSchemaParticle rootParticle, XmlSchemaObjectCollection attributes, XmlSchemaAnyAttribute anyAttribute, XmlQualifiedName baseTypeName, XmlSchemaAnnotation annotation)
   at System.Runtime.Serialization.SchemaImporter.ImportType(XmlSchemaType type, XmlQualifiedName typeName, Boolean isAnonymous)

Error message is somewhat misleading, but gives a clue that an exception thrown from this line:

runtime/src/libraries/System.Private.DataContractSerialization/src/System/Runtime/Serialization/SchemaImporter.cs

Line 1113 in a79c62d

ThrowArrayTypeCannotBeImportedException(typeName.Name, typeName.Namespace, SR.Format(SR.InvalidKeyValueTypeNamespace, element.Name, keyValueContract.Namespace));

Basically it looks like that namespaces are mismatched, but our xsd doesn't have any reference of 'http://schemas.datacontract.org/2004/07/System.Runtime.Serialization'.
during research and comparison of work of net4.8 execution path, I've figured out that problem is mismatch of namespaces resulting in following two lines:
new CollectionDataContract(Globals.TypeOfSchemaDefinedType, CollectionKind.Array) used in ImportCollection method gives contract namespace 'null', as in net4.8.
but
new ClassDataContract(Globals.TypeOfSchemaDefinedType) used in ImportClass method gives namespace 'http://schemas.datacontract.org/2004/07/System.Runtime.Serialization' mentioned in exception message and differs from net4.8 behavior.

Reproduction Steps

xsd:

            <xs:complexType name="ArrayOfKeyValueOfDayOfWeekbooleanRDHGY3MA">
                <xs:annotation>
                    <xs:appinfo>
                        <IsDictionary xmlns="http://schemas.microsoft.com/2003/10/Serialization/">true</IsDictionary>
                    </xs:appinfo>
                </xs:annotation>
                <xs:sequence>
                    <xs:element minOccurs="0" maxOccurs="unbounded" name="KeyValueOfDayOfWeekbooleanRDHGY3MA">
                        <xs:complexType>
                            <xs:sequence>
                                <xs:element xmlns:q1="http://schemas.datacontract.org/2004/07/System" name="Key"
                                            type="q1:DayOfWeek"/>
                                <xs:element name="Value" type="xs:boolean"/>
                            </xs:sequence>
                        </xs:complexType>
                    </xs:element>
                </xs:sequence>
            </xs:complexType>

C#

                XsdDataContractImporter importer = new XsdDataContractImporter();
                importer.Options = new ImportOptions();
                importer.Options.ImportXmlType = true;
                importer.Options.CodeProvider = codeProvider;
                importer.Options.ReferencedCollectionTypes.Add(typeof(List<>));
                importer.Options.ReferencedTypes.Add(typeof(Tuple<,>));
                importer.Import(xsds);

If you need copy-paste-and-run sample, pls give me a notice, as it is a part of 1mb complex xsd file, and narrow down only this complex type would take some effort.

Expected behavior

No exception occurs

Actual behavior

Exception occurs

System.Runtime.Serialization.InvalidDataContractException: Array type 'ArrayOfKeyValueOfDayOfWeekbooleanRDHGY3MA' in namespace 'http://schemas.microsoft.com/2003/10/Serialization/Arrays' cannot be imported. It is an invalid dictionary type since element 'KeyValueOfDayOfWeekbooleanRDHGY3MA' references a type from a different namespace 'http://schemas.datacontract.org/2004/07/System.Runtime.Serialization'. Either fix the schema or remove the IsDictionary annotation. Either change the schema so that the types can map to data contract types or use ImportXmlType or use a different serializer.
   at System.Runtime.Serialization.SchemaImporter.ThrowTypeCannotBeImportedException(String message)
   at System.Runtime.Serialization.SchemaImporter.ImportCollection(XmlQualifiedName typeName, XmlSchemaSequence rootSequence, XmlSchemaObjectCollection attributes, XmlSchemaAnnotation annotation, Boolean isReference)
   at System.Runtime.Serialization.SchemaImporter.ImportType(XmlQualifiedName typeName, XmlSchemaParticle rootParticle, XmlSchemaObjectCollection attributes, XmlSchemaAnyAttribute anyAttribute, XmlQualifiedName baseTypeName, XmlSchemaAnnotation annotation)
   at System.Runtime.Serialization.SchemaImporter.ImportType(XmlSchemaType type, XmlQualifiedName typeName, Boolean isAnonymous)

Regression?

No response

Known Workarounds

No response

Configuration

.net7.0 running on windows

    <PackageReference Include="System.Web.Services.Description" Version="8.0.0" />
    <PackageReference Include="System.Runtime.Serialization.Schema" Version="8.0.0" />

Other information

No response