ClangCodeModel: remove ClangdTextMark safety net

Since all text mark created by the diagnostic manager get deleted
properly on destruction now, there is no need to react on the client
destruction in ClangdTextMark.

Task-number: QTCREATORBUG-26585
Change-Id: Ifb9b8546c8f0d94debdcf2c8de6081e4e731cfab
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/clangcodemodel/clangtextmark.cpp

@@ -406,11 +406,6 @@ ClangdTextMark::ClangdTextMark(const FilePath &filePath,
         ClangDiagnosticManager::addTask(m_diagnostic);
     }
 
-    m_clientDeleted = QObject::connect(client, &QObject::destroyed, [this] (){
-        QTC_ASSERT_STRING("ClangdClient deleted before TextMark");
-        delete this;
-    });
-
     // Copy to clipboard action
     QVector<QAction *> actions;
     QAction *action = new QAction();
@@ -438,11 +433,6 @@ ClangdTextMark::ClangdTextMark(const FilePath &filePath,
     setActions(actions);
 }
 
-ClangdTextMark::~ClangdTextMark()
-{
-    QObject::disconnect(m_clientDeleted);
-}
-
 bool ClangdTextMark::addToolTipContent(QLayout *target) const
 {
     const auto canApplyFixIt = [c = m_client, diag = m_lspDiagnostic, fp = fileName()] {

src/plugins/clangcodemodel/clangtextmark.h

@@ -73,7 +73,6 @@ public:
     ClangdTextMark(const ::Utils::FilePath &filePath,
                    const LanguageServerProtocol::Diagnostic &diagnostic,
                    const LanguageClient::Client *client);
-    ~ClangdTextMark();
 
 private:
     bool addToolTipContent(QLayout *target) const override;
@@ -81,8 +80,6 @@ private:
     const LanguageServerProtocol::Diagnostic m_lspDiagnostic;
     const ClangBackEnd::DiagnosticContainer m_diagnostic;
     const QPointer<const LanguageClient::Client> m_client;
-
-    QMetaObject::Connection m_clientDeleted;
 };
 
 } // namespace Internal