GO-19393: Select the first node in the tree of the recent projects

The recent projects of non-modal welcome screen does not contain the current project, which is actually the recent one.
So instead, we should select the first visible node.

GitOrigin-RevId: 4a47f7a64bbee41042e4193cc265358e9a1f1148

platform/non-modal-welcome-screen/src/com/intellij/platform/ide/nonModalWelcomeScreen/leftPanel/WelcomeScreenLeftPanel.kt

@@ -136,7 +136,7 @@ class WelcomeScreenLeftPanel(private val project: Project) : ProjectViewPane(pro
       treeBackground = null
     ).apply {
       tree.emptyText.text = NonModalWelcomeScreenBundle.message("welcome.screen.no.recent.projects")
-      selectLastOpenedProject()
+      selectLastOpenedProjectOrTheFirstInTree()
     }
 
   private fun createProjectSearchField(recentProjectTree: RecentProjectFilteringTree): SearchTextField =

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/recentProjects/RecentProjectFilteringTree.kt

@@ -189,9 +189,12 @@ class RecentProjectFilteringTree(
     }
   }
 
-  fun selectLastOpenedProject() {
+  /**
+   * @return true if the last opened project was selected
+   */
+  fun selectLastOpenedProject(): Boolean {
     val recentProjectsManager = RecentProjectsManagerBase.getInstanceEx()
-    val projectPath = recentProjectsManager.getLastOpenedProject() ?: return
+    val projectPath = recentProjectsManager.getLastOpenedProject() ?: return false
 
     val node = TreeUtil.findNode(root, Condition {
       when (val item = TreeUtil.getUserObject(RecentProjectTreeItem::class.java, it)) {
@@ -203,7 +206,23 @@ class RecentProjectFilteringTree(
 
     if (node != null) {
       TreeUtil.selectNode(tree, node)
+      return true
     }
+    return false
+  }
+
+  @ApiStatus.Internal
+  fun selectLastOpenedProjectOrTheFirstInTree(): Boolean {
+    if (selectLastOpenedProject()) {
+      return true
+    }
+
+    val firstChild = root.firstChild
+    if (firstChild != null) {
+      TreeUtil.selectNode(tree, firstChild)
+      return true
+    }
+    return false
   }
 
   private class ProjectActionMouseListener(