VisualBuilder: Add [x, y, width, height] properties for all widgets.

At first I tried doing this as a single "rect" property but I like the
feel of the individual properties much better. :^)

Applications/VisualBuilder/VBProperty.h

@@ -10,6 +10,7 @@ public:
 
     String name() const { return m_name; }
     const GVariant& value() const { return m_value; }
+    void set_value(const GVariant& value) { m_value = value; }
 
     bool is_readonly() const { return m_readonly; }
     void set_readonly(bool b) { m_readonly = b; }

Applications/VisualBuilder/VBWidget.cpp

@@ -24,7 +24,10 @@ Rect VBWidget::rect() const
 
 void VBWidget::set_rect(const Rect& rect)
 {
+    if (rect == m_gwidget->relative_rect())
+        return;
     m_gwidget->set_relative_rect(rect);
+    synchronize_properties();
 }
 
 bool VBWidget::is_selected() const
@@ -74,3 +77,22 @@ void VBWidget::for_each_property(Function<void(VBProperty&)> callback)
         callback(*it);
     }
 }
+
+void VBWidget::synchronize_properties()
+{
+    property_by_name("width")->set_value(m_gwidget->width());
+    property_by_name("height")->set_value(m_gwidget->height());
+    property_by_name("x")->set_value(m_gwidget->x());
+    property_by_name("y")->set_value(m_gwidget->y());
+
+    m_property_model->update();
+}
+
+VBProperty* VBWidget::property_by_name(const String& name)
+{
+    for (auto& property : m_properties) {
+        if (property->name() == name)
+            return property.ptr();
+    }
+    return nullptr;
+}

Applications/VisualBuilder/VBWidget.h

@@ -51,10 +51,11 @@ public:
 
     VBWidgetPropertyModel& property_model() { return *m_property_model; }
 
-protected:
+    void synchronize_properties();
-    VBWidget(VBWidgetType, VBForm&);
 
 private:
+    VBWidget(VBWidgetType, VBForm&);
+
     VBWidgetType m_type { VBWidgetType::None };
     VBForm& m_form;
     GWidget* m_gwidget { nullptr };

Applications/VisualBuilder/VBWidgetPropertyModel.h

@@ -21,7 +21,7 @@ public:
     virtual String column_name(int column) const override;
     virtual ColumnMetadata column_metadata(int column) const override;
     virtual GVariant data(const GModelIndex&, Role = Role::Display) const override;
-    virtual void update() override { }
+    virtual void update() override { did_update(); }
 
 private:
     explicit VBWidgetPropertyModel(VBWidget&);

Applications/VisualBuilder/VBWidgetRegistry.cpp

@@ -73,15 +73,18 @@ static GWidget* build_gwidget(VBWidgetType type, GWidget* parent)
     }
 }
 
-
 GWidget* VBWidgetRegistry::build_gwidget(VBWidgetType type, GWidget* parent, Vector<OwnPtr<VBProperty>>& properties)
 {
     auto* gwidget = ::build_gwidget(type, parent);
-    auto add_property = [&properties] (const String& name, const GVariant& value, bool is_readonly) {
+    auto add_property = [&properties] (const String& name, const GVariant& value = { }, bool is_readonly = false) {
         auto property = make<VBProperty>(name, value);
         property->set_readonly(is_readonly);
         properties.append(move(property));
     };
     add_property("class", to_class_name(type), true);
+    add_property("width");
+    add_property("height");
+    add_property("x");
+    add_property("y");
     return gwidget;
 }