Replace slots with Q_SLOTS

src/musicbrainz/acoustidclient.h

@@ -63,7 +63,7 @@ class AcoustidClient : public QObject {
  Q_SIGNALS:
   void Finished(const int id, const QStringList &mbid_list, const QString &error = QString());
 
- private slots:
+ private Q_SLOTS:
   void RequestFinished(QNetworkReply *reply, const int id);
 
  private:

src/musicbrainz/musicbrainzclient.h

@@ -107,7 +107,7 @@ class MusicBrainzClient : public QObject {
   // Finished signal emitted when fechting album's songs tags using DiscId
   void DiscIdFinished(const QString &artist, const QString &album, const MusicBrainzClient::ResultList &result, const QString &error = QString());
 
- private slots:
+ private Q_SLOTS:
   void FlushRequests();
   // id identifies the track, and request_number means it's the 'request_number'th request for this track
   void RequestFinished(QNetworkReply *reply, const int id, const int request_number);

src/musicbrainz/tagfetcher.h

@@ -46,14 +46,14 @@ class TagFetcher : public QObject {
 
   void StartFetch(const SongList &songs);
 
- public slots:
+ public Q_SLOTS:
   void Cancel();
 
  Q_SIGNALS:
   void Progress(const Song &original_song, const QString &stage);
   void ResultAvailable(const Song &original_song, const SongList &songs_guessed, const QString &error = QString());
 
- private slots:
+ private Q_SLOTS:
   void FingerprintFound(const int index);
   void PuidsFound(const int index, const QStringList &puid_list, const QString &error = QString());
   void TagsFetched(const int index, const MusicBrainzClient::ResultList &results, const QString &error = QString());