QmlDesigner: Fix not loading assets in some cases

When user creates new project in the same QDS session,
assets view were empty.

Fixes: QDS-14523
Change-Id: Ifc56e85b556b73eaf8d29fff031e207e8f9ee182
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Shrief Gabr <shrief.gabr@qt.io>
(cherry picked from commit 6f5debb5f5)
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

share/qtcreator/qmldesigner/assetsLibraryQmlSources/AssetsView.qml

@@ -136,8 +136,7 @@ TreeView {
             // view: make sure we will do an "expand all" (otherwise, the whole tree might
             // be collapsed, and with our visible root not being the actual root of the tree,
             // the entire tree would be invisible)
-            root.lastRowCount = -1
-            root.requestedExpandAll = true
+            root.reset()
         }
 
         function onFileChanged(filePath)
@@ -154,6 +153,17 @@ TreeView {
 
     } // Connections
 
+    // Resets everything to its default state before reusing the widget
+    function reset()
+    {
+        root.lastRowCount = -1
+        root.rootPathDepth = 0
+        root.rootPathRow = 0
+        root.requestedExpandAll = true
+        // Attempt to force reload
+        updateRowsTimer.restart()
+    }
+
     function addCreatedFolder(path)
     {
         root.__createdDirectories.push(path)