Use explicit c'tor in all Qt Widgets GUI related classes

tray/gui/devbuttonsitemdelegate.h

@@ -9,7 +9,7 @@ namespace QtGui {
 class DevButtonsItemDelegate : public QStyledItemDelegate {
     Q_OBJECT
 public:
-    DevButtonsItemDelegate(QObject *parent);
+    explicit DevButtonsItemDelegate(QObject *parent);
 
     void paint(QPainter *, const QStyleOptionViewItem &, const QModelIndex &) const override;
 };

tray/gui/devview.h

@@ -17,7 +17,7 @@ public:
     using ModelType = Data::SyncthingDeviceModel;
     using SortFilterModelType = Data::SyncthingSortFilterModel;
 
-    DevView(QWidget *parent = nullptr);
+    explicit DevView(QWidget *parent = nullptr);
 
 Q_SIGNALS:
     void pauseResumeDev(const Data::SyncthingDev &dev);

tray/gui/dirbuttonsitemdelegate.h

@@ -8,7 +8,7 @@ namespace QtGui {
 class DirButtonsItemDelegate : public QStyledItemDelegate {
     Q_OBJECT
 public:
-    DirButtonsItemDelegate(QObject *parent);
+    explicit DirButtonsItemDelegate(QObject *parent);
 
     void paint(QPainter *, const QStyleOptionViewItem &, const QModelIndex &) const override;
 };

tray/gui/dirview.h

@@ -17,7 +17,7 @@ public:
     using ModelType = Data::SyncthingDirectoryModel;
     using SortFilterModelType = Data::SyncthingSortFilterModel;
 
-    DirView(QWidget *parent = nullptr);
+    explicit DirView(QWidget *parent = nullptr);
 
 Q_SIGNALS:
     void openDir(const Data::SyncthingDir &dir);

tray/gui/downloaditemdelegate.h

@@ -9,7 +9,7 @@ namespace QtGui {
 class DownloadItemDelegate : public QStyledItemDelegate {
     Q_OBJECT
 public:
-    DownloadItemDelegate(QObject *parent);
+    explicit DownloadItemDelegate(QObject *parent);
 
     void paint(QPainter *, const QStyleOptionViewItem &, const QModelIndex &) const override;
     QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const override;

tray/gui/downloadview.h

@@ -17,7 +17,7 @@ public:
     using ModelType = Data::SyncthingDownloadModel;
     using SortFilterModelType = void;
 
-    DownloadView(QWidget *parent = nullptr);
+    explicit DownloadView(QWidget *parent = nullptr);
 
 Q_SIGNALS:
     void openDir(const Data::SyncthingDir &dir);

tray/gui/trayicon.h

@@ -28,7 +28,7 @@ class TrayIcon : public QSystemTrayIcon {
     Q_OBJECT
 
 public:
-    TrayIcon(const QString &connectionConfig = QString(), QObject *parent = nullptr);
+    explicit TrayIcon(const QString &connectionConfig = QString(), QObject *parent = nullptr);
     TrayMenu &trayMenu();
 
 public Q_SLOTS:

tray/gui/traywidget.h

@@ -51,7 +51,7 @@ class TrayWidget : public QWidget {
     Q_OBJECT
 
 public:
-    TrayWidget(TrayMenu *parent = nullptr);
+    explicit TrayWidget(TrayMenu *parent = nullptr);
     ~TrayWidget() override;
 
     Data::SyncthingConnection &connection();