CanDelete is necessary for dimensions

- therefore revert commit bd0bf690b53f8355400278a127524029d225dffb.
- handle balloons the same way
- fix line ending in ViewProviderProjGroupItem.cpp

src/Mod/TechDraw/Gui/ViewProviderBalloon.cpp

@@ -180,3 +180,11 @@ void ViewProviderBalloon::handleChangedPropertyType(Base::XMLReader &reader, con
         LineWidth.setValue(LineWidthProperty.getValue());
     }
 }
+
+bool ViewProviderBalloon::canDelete(App::DocumentObject *obj) const
+{
+    // deletions of a balloon object doesn't destroy anything
+    // thus we can pass this action
+    Q_UNUSED(obj)
+    return true;
+}

src/Mod/TechDraw/Gui/ViewProviderBalloon.h

@@ -60,6 +60,7 @@ public:
     virtual bool setEdit(int ModNum);
     virtual void unsetEdit(int ModNum);
     virtual bool doubleClicked(void);
+    virtual bool canDelete(App::DocumentObject* obj) const;
 
     virtual TechDraw::DrawViewBalloon* getViewObject() const;
 

src/Mod/TechDraw/Gui/ViewProviderDimension.cpp

@@ -221,3 +221,11 @@ void ViewProviderDimension::handleChangedPropertyType(Base::XMLReader &reader, c
         LineWidth.setValue(LineWidthProperty.getValue());
     }
 }
+
+bool ViewProviderDimension::canDelete(App::DocumentObject *obj) const
+{
+    // deletions of dimension objects don't destroy anything
+    // thus we can pass this action
+    Q_UNUSED(obj)
+    return true;
+}

src/Mod/TechDraw/Gui/ViewProviderDimension.h

@@ -80,6 +80,7 @@ public:
     double prefFontSize() const;
     double prefWeight() const;
     int prefStandardAndStyle() const;
+    virtual bool canDelete(App::DocumentObject* obj) const;
 
 protected:
     virtual void handleChangedPropertyType(Base::XMLReader &reader, const char *TypeName, App::Property * prop);

src/Mod/TechDraw/Gui/ViewProviderProjGroupItem.cpp

@@ -43,7 +43,7 @@
 #include <Gui/Document.h>
 #include <Gui/MainWindow.h>
 
-#include <Mod/TechDraw/App/DrawProjGroup.h>
+#include <Mod/TechDraw/App/DrawProjGroup.h>
 #include <Mod/TechDraw/App/DrawProjGroupItem.h>
 
 #include "ViewProviderProjGroupItem.h"
@@ -153,7 +153,7 @@ bool ViewProviderProjGroupItem::onDelete(const std::vector<std::string> &)
     bool isAnchor = false;
 
     // get the item and group
-    TechDraw::DrawProjGroupItem* dpgi = static_cast<TechDraw::DrawProjGroupItem*>(getViewObject());
+    TechDraw::DrawProjGroupItem* dpgi = static_cast<TechDraw::DrawProjGroupItem*>(getViewObject());
     TechDraw::DrawProjGroup* dpg = dpgi->getPGroup();
     // get the projection
     TechDraw::DrawProjGroupItem* proj = getObject();