Make changing marker color undoable

app/widget/marker/markerundo.cpp

@@ -66,4 +66,27 @@ void MarkerRemoveCommand::undo()
   marker_list_->AddMarker(range_, name_, color_);
 }
 
+MarkerChangeColorCommand::MarkerChangeColorCommand(Project *project, TimelineMarker *marker, int new_color) :
+    project_(project),
+    marker_(marker),
+    old_color_(marker->color()),
+    new_color_(new_color)
+{
+}
+
+Project* MarkerChangeColorCommand::GetRelevantProject() const
+{
+  return project_;
+}
+
+void MarkerChangeColorCommand::redo()
+{
+  marker_->set_color(new_color_);
+}
+
+void MarkerChangeColorCommand::undo()
+{
+  marker_->set_color(old_color_);
+}
+
 }

app/widget/marker/markerundo.h

@@ -61,6 +61,23 @@ class MarkerRemoveCommand : public UndoCommand {
     int color_;
 };
 
+class MarkerChangeColorCommand : public UndoCommand {
+  public:
+    MarkerChangeColorCommand(Project* project, TimelineMarker* marker, int new_color);
+
+    virtual Project* GetRelevantProject() const override;
+
+  protected:
+    virtual void redo() override;
+    virtual void undo() override;
+
+  private:
+    Project* project_;
+    TimelineMarker* marker_;
+    int old_color_;
+    int new_color_;
+};
+
 }
 
 #endif  // TIMELINEUNDOTRACK_H

app/widget/timeruler/seekablewidget.cpp

@@ -232,9 +232,13 @@ void SeekableWidget::removeMarker(TimelineMarker *marker)
 
 void SeekableWidget::SetMarkerColor(int c)
 {
+  MultiUndoCommand *command = new MultiUndoCommand();
+
   foreach(TimelineMarker* marker, GetActiveTimelineMarkers()) {
-    marker->set_color(c);
+    command->add_child(new MarkerChangeColorCommand(Core::instance()->GetActiveProject(), marker, c));
   }
+
+  Core::instance()->undo_stack()->pushIfHasChildren(command);
 }
 
 void SeekableWidget::updateMarkerPositions()