PDF: add support for the Author field

[ChangeLog][QtGui][QPdfWriter] It is now possible to set the Author
information for a PDF file.

Change-Id: I27cb409d37cb79d9476a4da0c82d4a6d35f5fe8d
Reviewed-by: Albert Astals Cid <aacid@kde.org>

src/gui/painting/qpdf.cpp

@@ -1742,6 +1742,8 @@ void QPdfEnginePrivate::writeInfo(const QDateTime &date)
     printString(title);
     write("\n/Creator ");
     printString(creator);
+    write("\n/Author ");
+    printString(author);
     write("\n/Producer ");
     printString(QString::fromLatin1("Qt " QT_VERSION_STR));
 
@@ -1847,6 +1849,13 @@ int QPdfEnginePrivate::writeXmpDocumentMetaData(const QDateTime &date)
                     w.writeEndElement();
                 w.writeEndElement();
             w.writeEndElement();
+            w.writeStartElement(dcNS, "creator");
+                w.writeStartElement(rdfNS, "Seq");
+                    w.writeStartElement(rdfNS, "li");
+                        w.writeCharacters(author);
+                    w.writeEndElement();
+                w.writeEndElement();
+            w.writeEndElement();
         w.writeEndElement();
 
         // PDF

src/gui/painting/qpdf_p.h

@@ -265,6 +265,7 @@ public:
     QString outputFileName;
     QString title;
     QString creator;
+    QString author;
     QUuid documentId = QUuid::createUuid();
     bool embedFonts;
     int resolution;

src/gui/painting/qpdfwriter.cpp

@@ -211,6 +211,26 @@ void QPdfWriter::setDocumentId(const QUuid &documentId)
     d->engine->d_func()->documentId = documentId;
 }
 
+/*!
+  \since 6.9
+  Returns the author of the document.
+  */
+QString QPdfWriter::author() const
+{
+    Q_D(const QPdfWriter);
+    return d->engine->d_func()->author;
+}
+
+/*!
+  \since 6.9
+  Sets the author of the document to \a author.
+  */
+void QPdfWriter::setAuthor(const QString &author)
+{
+    Q_D(QPdfWriter);
+    d->engine->d_func()->author = author;
+}
+
 /*!
   \reimp
   */

src/gui/painting/qpdfwriter.h

@@ -39,6 +39,9 @@ public:
     QUuid documentId() const;
     void setDocumentId(const QUuid &documentId);
 
+    QString author() const;
+    void setAuthor(const QString &author);
+
     bool newPage() override;
 
     void setResolution(int resolution);