Docking: Fixed another issue where the resulting node of a split would sometimes recall the pos/size of previous host window. Spent a whole day adding framework for testing more of docking so hopefully we'll heading toward the magical world of less regressions. (#2109)

imgui.cpp

@@ -11838,6 +11838,7 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
             ImGuiWindow* single_window = node->Windows[0];
             node->Pos = single_window->Pos;
             node->Size = single_window->SizeFull;
+            node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Window;
 
             // Transfer focus immediately so when we revert to a regular window it is immediately selected
             if (node->HostWindow && g.NavWindow == node->HostWindow)
@@ -11855,7 +11856,6 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
         }
 
         DockNodeHideHostWindow(node);
-        node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Window;
         node->WantCloseAll = false;
         node->WantCloseTabID = 0;
         node->HasCloseButton = node->HasCollapseButton = false;
@@ -12664,6 +12664,7 @@ void ImGui::DockNodeTreeSplit(ImGuiContext* ctx, ImGuiDockNode* parent_node, ImG
     parent_node->ChildNodes[split_inheritor_child_idx]->VisibleWindow = parent_node->VisibleWindow;
     parent_node->SplitAxis = split_axis;
     parent_node->VisibleWindow = NULL;
+    parent_node->AuthorityForPos = parent_node->AuthorityForSize = ImGuiDataAuthority_DockNode;
 
     float size_avail = (parent_node->Size[split_axis] - IMGUI_DOCK_SPLITTER_SIZE);
     size_avail = ImMax(size_avail, g.Style.WindowMinSize[split_axis] * 2.0f);