rm unneeded forward declarations, especially of SessionItem

GUI/Model/Descriptor/UIntProperty.h

@@ -20,7 +20,6 @@
 #include <variant>
 
 class Streamer;
-class SessionItem;
 
 //! Class for representing a uint value, its attributes and its accessors.
 //!

GUI/View/Import/RealDataSelectorWidget.cpp

@@ -29,12 +29,10 @@
 #include "GUI/View/Info/MessageBox.h"
 #include "GUI/View/Project/ProjectManager.h"
 #include <QFileDialog>
-#include <QItemSelectionModel>
 #include <QLineEdit>
 #include <QListView>
 #include <QMenu>
 #include <QSplitter>
-#include <QTreeView>
 #include <QVBoxLayout>
 
 RealDataSelectorWidget::RealDataSelectorWidget(QWidget* parent, ProjectDocument* document)

GUI/View/Import/RealDataSelectorWidget.h

@@ -15,7 +15,9 @@
 #ifndef BORNAGAIN_GUI_VIEW_IMPORT_REALDATASELECTORWIDGET_H
 #define BORNAGAIN_GUI_VIEW_IMPORT_REALDATASELECTORWIDGET_H
 
+#include <QItemSelectionModel>
 #include <QModelIndex>
+#include <QTreeView>
 #include <QWidget>
 #include <functional>
 
@@ -23,12 +25,9 @@ class RealDataPropertiesWidget;
 class RealDataItemSelectorWidget;
 class InstrumentCollection;
 class RealModel;
-class SessionItem;
 class RealDataSelectorActions;
 class RealItem;
 class RealDataTreeModel;
-class QItemSelection;
-class QTreeView;
 class ProjectDocument;
 
 //! The RealDataSelectorWidget represents left panel of ImportDataView. Contains a tree to

GUI/View/Instrument/DistributionPlot.cpp

@@ -19,7 +19,6 @@
 #include "GUI/View/Info/CautionSign.h"
 #include "Param/Distrib/Distributions.h"
 #include "qcustomplot.h"
-#include <QLabel>
 #include <QVBoxLayout>
 #include <algorithm>
 

GUI/View/Instrument/DistributionPlot.h

@@ -16,15 +16,14 @@
 #define BORNAGAIN_GUI_VIEW_INSTRUMENT_DISTRIBUTIONPLOT_H
 
 #include "qcustomplot.h"
+#include <QAction>
+#include <QLabel>
 #include <QWidget>
 
-class SessionItem;
-class QLabel;
-class QCustomPlot;
+class CautionSign;
 class DistributionItem;
-class QAction;
+class QCustomPlot;
 class RealLimits;
-class CautionSign;
 
 //! The DistributionPlot class plots 1d functions corresponding to domain's Distribution1D
 class DistributionPlot : public QWidget {

GUI/View/Mask/IShape2DView.cpp

@@ -19,7 +19,6 @@
 #include <QGraphicsScene>
 #include <QGraphicsSceneContextMenuEvent>
 #include <QMenu>
-#include <QPainter>
 
 namespace {
 

GUI/View/Mask/IShape2DView.h

@@ -17,11 +17,11 @@
 
 #include "GUI/View/Mask/MaskEditorHelper.h"
 #include <QGraphicsObject>
+#include <QPainter>
 
-class SessionItem;
 class MaskItemObject;
 class ISceneAdaptor;
-class QPainter;
+class SessionItem;
 
 //! Main interface class for views representing MaskItems, Projections on graphics scene.
 

GUI/View/Plot2D/IntensityDataWidget.h

@@ -16,11 +16,10 @@
 #define BORNAGAIN_GUI_VIEW_PLOT2D_INTENSITYDATAWIDGET_H
 
 #include "GUI/View/Common/DataAccessWidget.h"
+#include <QAction>
 
-class SessionItem;
 class IntensityDataCanvas;
 class IntensityDataPropertyWidget;
-class QAction;
 class IntensityDataFFTPresenter;
 
 //! A common widget to display color map (IntensityDataCanvas) and properties

GUI/View/SampleDesigner/LayerOrientedSampleEditor.cpp

@@ -24,7 +24,6 @@
 #include <QActionGroup>
 #include <QBoxLayout>
 #include <QPushButton>
-#include <QScrollArea>
 
 LayerOrientedSampleEditor::LayerOrientedSampleEditor(QWidget* parent, ProjectDocument* document)
     : QWidget(parent)

GUI/View/SampleDesigner/LayerOrientedSampleEditor.h

@@ -16,16 +16,15 @@
 #define BORNAGAIN_GUI_VIEW_SAMPLEDESIGNER_LAYERORIENTEDSAMPLEEDITOR_H
 
 #include <QMap>
+#include <QScrollArea>
+#include <QToolBar>
 #include <QWidget>
 
 class Item3D;
 class MultiLayerForm;
 class MultiLayerItem;
 class ProjectDocument;
-class QScrollArea;
-class QToolBar;
 class SampleEditorController;
-class SessionItem;
 
 //! Sample editor with layer oriented presentation of a sample
 class LayerOrientedSampleEditor : public QWidget {

GUI/View/SampleDesigner/SampleEditorController.h

@@ -39,7 +39,6 @@ class MultiLayerItem;
 class ParticleLayoutItem;
 class ProjectDocument;
 class SelectionContainerForm;
-class SessionItem;
 class UIntDescriptor;
 
 //! Class to modify a sample from the layer oriented sample editor.

GUI/View/SampleDesigner/SampleView.h

@@ -19,11 +19,9 @@
 
 class DocksController;
 class Item3D;
-class MultiLayerItem;
 class ProjectDocument;
 class RealspacePanel;
 class SampleListView;
-class SessionItem;
 
 class SampleView : public QMainWindow {
     Q_OBJECT

GUI/View/Toplevel/SessionDecorationModel.h

@@ -18,7 +18,6 @@
 #include <QIdentityProxyModel>
 
 class SessionModel;
-class SessionItem;
 
 //! Provides decorations (text color, icons, etc) for SessionModel in SessionModelView context.
 //! It is implemented as identity proxy model, so it has one-to-one data structure as in