New context with albums and lyrics +++ much more

* Added new lyrics provider with lyrics from AudD and API Seeds
* New improved context widget with albums and lyrics
* Fixed playing and context widget getting stuck in play mode when there was an error
* Changed icons for artists in collection, tidal and cover manager
* Removed "search" icon from "Search automatically" checkbox (right click) that looked ugly
* Removed some unused widgets from the src/widgets directory
* Fixed initial size of window and side panel
* Fixed saving window size correctly

src/context/contextalbumsview.h

@@ -0,0 +1,151 @@
+/*
+ * Strawberry Music Player
+ * This code was part of Clementine.
+ * Copyright 2010, David Sansome <me@davidsansome.com>
+ * Copyright 2013, Jonas Kvinge <jonas@strawbs.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef CONTEXTALBUMSVIEW_H
+#define CONTEXTALBUMSVIEW_H
+
+#include "config.h"
+
+#include <memory>
+#include <stdbool.h>
+
+#include <QObject>
+#include <QWidget>
+#include <QAbstractItemModel>
+#include <QAbstractItemView>
+#include <QString>
+#include <QPixmap>
+#include <QPainter>
+#include <QSet>
+#include <QStyleOption>
+#include <QStyledItemDelegate>
+#include <QStyleOptionViewItem>
+#include <QAction>
+#include <QMenu>
+#include <QtEvents>
+
+#include "core/song.h"
+#include "widgets/autoexpandingtreeview.h"
+
+class Application;
+class EditTagDialog;
+#ifdef HAVE_GSTREAMER
+class OrganiseDialog;
+#endif
+class ContextAlbumsModel;
+
+class ContextItemDelegate : public QStyledItemDelegate {
+  Q_OBJECT
+
+ public:
+  ContextItemDelegate(QObject *parent);
+  void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const;
+
+ public slots:
+  bool helpEvent(QHelpEvent *event, QAbstractItemView *view, const QStyleOptionViewItem &option, const QModelIndex &index);
+};
+
+class ContextAlbumsView : public AutoExpandingTreeView {
+  Q_OBJECT
+
+ public:
+  ContextAlbumsView(QWidget *parent = nullptr);
+  ~ContextAlbumsView();
+
+  // Returns Songs currently selected in the collection view.
+  // Please note that the selection is recursive meaning that if for example an album is selected this will return all of it's songs.
+  SongList GetSelectedSongs() const;
+
+  void SetApplication(Application *app);
+
+  // QTreeView
+  void scrollTo(const QModelIndex &index, ScrollHint hint = EnsureVisible);
+  
+  ContextAlbumsModel *albums_model() { return model_; }
+
+ public slots:
+  void ReloadSettings();
+
+  void SaveFocus();
+  void RestoreFocus();
+
+signals:
+  void ShowConfigDialog();
+
+ protected:
+  // QWidget
+  void paintEvent(QPaintEvent *event);
+  void mouseReleaseEvent(QMouseEvent *e);
+  void contextMenuEvent(QContextMenuEvent *e);
+
+ private slots:
+  void Load();
+  void AddToPlaylist();
+  void AddToPlaylistEnqueue();
+  void OpenInNewPlaylist();
+#ifdef HAVE_GSTREAMER
+  void Organise();
+  void CopyToDevice();
+#endif
+  void EditTracks();
+  void ShowInBrowser();
+
+ private:
+  void RecheckIsEmpty();
+  bool RestoreLevelFocus(const QModelIndex &parent = QModelIndex());
+  void SaveContainerPath(const QModelIndex &child);
+
+ private:
+  Application *app_;
+
+  QMenu *context_menu_;
+  QModelIndex context_menu_index_;
+  QAction *load_;
+  QAction *add_to_playlist_;
+  QAction *add_to_playlist_enqueue_;
+  QAction *open_in_new_playlist_;
+#ifdef HAVE_GSTREAMER
+  QAction *organise_;
+  QAction *copy_to_device_;
+#endif
+  QAction *delete_;
+  QAction *edit_track_;
+  QAction *edit_tracks_;
+  QAction *show_in_browser_;
+
+#ifdef HAVE_GSTREAMER
+  std::unique_ptr<OrganiseDialog> organise_dialog_;
+#endif
+  std::unique_ptr<EditTagDialog> edit_tag_dialog_;
+
+  bool is_in_keyboard_search_;
+
+  // Save focus
+  Song last_selected_song_;
+  QString last_selected_container_;
+  QSet<QString> last_selected_path_;
+  
+  ContextAlbumsModel *model_;
+  
+};
+
+#endif  // CONTEXTALBUMSVIEW_H
+