ProjectTree: Fix crash working with resources

Fix the notification of subtree changes to keep the project in
the loop, so that it can adjust its list of known files.

Ignoring that will cause crashes, e.g. when the ResourceEditor
updates its subtree of the project.

Task-number: QTCREATORBUG-19613
Change-Id: Ib7bb9afe48eb248cdf675ba2093b266fd728d7b2
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/projectexplorer/projectnodes.cpp

@@ -628,7 +628,7 @@ bool FolderNode::replaceSubtree(Node *oldNode, Node *newNode)
         }
         QTimer::singleShot(0, [oldNode]() { delete oldNode; });
     }
-    ProjectTree::emitSubtreeChanged(this);
+    handleSubTreeChanged(this);
     return true;
 }
 
@@ -879,6 +879,12 @@ bool FolderNode::isEmpty() const
     return m_nodes.isEmpty();
 }
 
+void FolderNode::handleSubTreeChanged(FolderNode *node)
+{
+    if (FolderNode *parent = parentFolderNode())
+        parent->handleSubTreeChanged(node);
+}
+
 ContainerNode::ContainerNode(Project *project)
     : FolderNode(project->projectDirectory(), NodeType::Project), m_project(project)
 {}
@@ -915,4 +921,9 @@ void ContainerNode::removeAllChildren()
     m_nodes.clear();
 }
 
+void ContainerNode::handleSubTreeChanged(FolderNode *node)
+{
+    m_project->handleSubTreeChanged(node);
+}
+
 } // namespace ProjectExplorer