Merge branch 'add-root-tree-line-option' of https://github.com/Tryibion/FlaxEngine into Tryibion-add-root-tree-line-option

Source/Editor/Windows/Assets/PrefabWindow.Hierarchy.cs

@@ -56,6 +56,7 @@ namespace FlaxEditor.Windows.Assets
             public PrefabTree()
             : base(true)
             {
+                DrawRootTreeLine = false;
             }
         }
 

Source/Editor/Windows/SceneTreeWindow.cs

@@ -85,6 +85,7 @@ namespace FlaxEditor.Windows
             {
                 Margin = new Margin(0.0f, 0.0f, -16.0f, _sceneTreePanel.ScrollBarsSize), // Hide root node
                 IsScrollable = true,
+                DrawRootTreeLine = false,
             };
             _tree.AddChild(root.TreeNode);
             _tree.SelectedChanged += Tree_OnSelectedChanged;