Move the parsing of the media type to isXMLMediaType

entry.go

@@ -4,7 +4,6 @@ import (
 	"encoding/xml"
 	"errors"
 	"fmt"
-	"mime"
 	"strings"
 )
 
@@ -144,10 +143,7 @@ func (e *Entry) Check() error {
 		// "type" attribute of atom:content is a MIME media type [MIMEREG], but
 		// is not an XML media type [RFC3023], does not begin with "text/", and
 		// does not end with "/xml" or "+xml".
-		mediaType, _, err := mime.ParseMediaType(e.Content.getType())
-		if err != nil {
-			return fmt.Errorf("type attribute of content element of entry %v: %v", e.ID.URI, err)
-		}
+		mediaType := e.Content.getType()
 		if !isXMLMediaType(mediaType) && !strings.HasPrefix(mediaType, "text/") {
 			return fmt.Errorf("no summary element of entry %v but media type not xml", e.ID.URI)
 		}