DrawPathTool: Fix crash introduced by object highlighting

Closing a path with Enter key or aborting the drawing procedure with
Escape causes Mapper crash on stale renerables further down the drawing.
The simple "following = false" is no longer enough to finish object
following. We need to remove the highlight renderables whish is done in
finishFollowing().

src/tools/draw_path_tool.cpp

@@ -916,7 +916,7 @@ void DrawPathTool::finishDrawing()
 	}
 
 	dragging = false;
-	following = false;
+	finishFollowing();
 	setEditingInProgress(false);
 	if (!ctrl_pressed)
 		angle_helper->setActive(false);
@@ -932,7 +932,7 @@ void DrawPathTool::finishDrawing()
 void DrawPathTool::abortDrawing()
 {
 	dragging = false;
-	following = false;
+	finishFollowing();
 	setEditingInProgress(false);
 	if (!ctrl_pressed)
 		angle_helper->setActive(false);