public RuntimeLibrary(IMetadataImporter metadataImporter, IErrorReporter errorReporter, ICompilation compilation, INamer namer)
 {
     _metadataImporter   = metadataImporter;
     _errorReporter      = errorReporter;
     _compilation        = compilation;
     _namer              = namer;
     _omitDowncasts      = MetadataUtils.OmitDowncasts(compilation);
     _omitNullableChecks = MetadataUtils.OmitNullableChecks(compilation);
 }