Make IDocument::fileName a member with setter.

Instead of requiring subclasses to implement a method.
Also renames IDocument::rename to IDocument::setFileName,
since it doesn't really rename any files or such.

Change-Id: I1344025c24d2f74a6a983e04fb0a5245f1f37aad
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/coreplugin/idocument.cpp

@@ -34,6 +34,13 @@
 #include <QFile>
 #include <QFileInfo>
 
+/*!
+    \fn QString Core::IDocument::fileName() const
+    Returns the absolute path of the file that this document refers to. May be empty for
+    non-file documents.
+    \sa setFileName()
+*/
+
 namespace Core {
 
 IDocument::IDocument(QObject *parent) : QObject(parent), m_infoBar(0), m_hasWriteWarning(false), m_restored(false)
@@ -110,4 +117,20 @@ InfoBar *IDocument::infoBar()
     return m_infoBar;
 }
 
+/*!
+    Set absolute file path for this file to \a fileName. Can be empty.
+    The default implementation sets the file name and sends fileNameChanged() and changed()
+    signals. Can be reimplemented by subclasses to do more.
+    \sa fileName()
+*/
+void IDocument::setFileName(const QString &fileName)
+{
+    if (m_fileName == fileName)
+        return;
+    QString oldName = m_fileName;
+    m_fileName = fileName;
+    emit fileNameChanged(oldName, m_fileName);
+    emit changed();
+}
+
 } // namespace Core