Dock system selection improvements and fixes (#14305)

* Make sure we don't trigger another select when a view in the project tree is selected.
* Fix for #14255 and related issues
* Make sure we can close and open a main window, keeping the layout when reopened.

ApplicationLibCode/Commands/ApplicationCommands/RicShowMainWindowFeature.cpp

@@ -37,7 +37,7 @@ void RicShowMainWindowFeature::showMainWindow()
 {
     RiuMainWindow* mainWnd = RiuMainWindow::instance();
 
-    if ( mainWnd )
+    if ( mainWnd != nullptr )
     {
         if ( mainWnd->isMinimized() )
         {
@@ -54,7 +54,7 @@ void RicShowMainWindowFeature::showMainWindow()
     else
     {
         RiaGuiApplication* app = RiaGuiApplication::instance();
-        app->getOrCreateAndShowMainWindow();
+        mainWnd                = app->getOrCreateAndShowMainWindow();
 
         // When the main window is created, make sure all the views are loaded and displayed
 
@@ -70,6 +70,10 @@ void RicShowMainWindowFeature::showMainWindow()
                 }
             }
         }
+        if ( mainWnd )
+        {
+            mainWnd->restoreDockWidgetState( RimProject::current()->mainWindowDockState );
+        }
     }
 }