ClangModelManagerSupport: Skip explicit call to waitForFinished()

This is done by the FutureSynchronizer d'tor, so no need to call
it explicitly. Move the FutureSynchronizer as the last field of
ClangModelManagerSupport so that its d'tor is executed first.

Change-Id: Id38b8ec08579be8e4ade99ecadb511850ff37f8c
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -293,10 +293,7 @@ ClangModelManagerSupport::ClangModelManagerSupport()
     new ClangdQuickFixFactory(); // memory managed by CppEditor::g_cppQuickFixFactories
 }
 
-ClangModelManagerSupport::~ClangModelManagerSupport()
-{
-    m_generatorSynchronizer.waitForFinished();
-}
+ClangModelManagerSupport::~ClangModelManagerSupport() = default;
 
 void ClangModelManagerSupport::followSymbol(const CursorInEditor &data,
                                             const LinkHandler &processLinkCallback,

src/plugins/clangcodemodel/clangmodelmanagersupport.h

@@ -94,10 +94,10 @@ private:
     void scheduleClientRestart(ClangdClient *client);
     static ClangdClient *clientWithProject(const ProjectExplorer::Project *project);
 
-    Utils::FutureSynchronizer m_generatorSynchronizer;
     QList<QPointer<ClangdClient>> m_clientsToRestart;
     QTimer * const m_clientRestartTimer;
     QHash<Utils::FilePath, QString> m_potentialShadowDocuments;
+    Utils::FutureSynchronizer m_generatorSynchronizer; // Keep me last
 };
 
 } // namespace Internal