ClangFormat: Fix General tab is missing

Fixes: QTCREATORBUG-30501
Change-Id: Ic1f09e513114acf6fb6ee52c8b5f066a2071e202
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/clangformat/clangformatglobalconfigwidget.cpp

@@ -277,6 +277,7 @@ void ClangFormatGlobalConfigWidget::initCustomSettingsCheckBox()
             !m_useCustomSettingsCheckBox->isChecked());
         m_codeStyle->currentPreferences()->setIsAdditionalTabVisible(
             m_useCustomSettingsCheckBox->isEnabled());
+        m_codeStyle->currentPreferences()->setAdditionalTabExist(true);
         ClangFormatSettings::instance().write();
         emit m_codeStyle->currentPreferencesChanged(m_codeStyle->currentPreferences());
     };

src/plugins/cppeditor/cppcodestylesettingspage.cpp

@@ -429,9 +429,11 @@ void CppCodeStylePreferencesWidget::slotCurrentPreferencesChanged(ICodeStylePref
     const bool enable = !preferences->isReadOnly() && (!preferences->isTemporarilyReadOnly()
                                                        || !preferences->isAdditionalTabVisible());
 
+    if (preferences->additionalTabExist()) {
         d->m_categoryTab->setTabVisible(0, preferences->isAdditionalTabVisible());
         for (int i = 1; i < d->m_categoryTab->count(); ++i)
             d->m_categoryTab->setTabVisible(i, !preferences->isAdditionalTabVisible());
+    }
 
     for (QWidget *widget : d->m_controllers)
         widget->setEnabled(enable);

src/plugins/texteditor/icodestylepreferences.cpp

@@ -25,6 +25,7 @@ public:
     bool m_readOnly = false;
     bool m_temporarilyReadOnly = false;
     bool m_isAdditionalTabVisible = false;
+    bool m_isAdditionalTabExist = false;
     Key m_settingsSuffix;
 };
 
@@ -92,6 +93,16 @@ void ICodeStylePreferences::setIsAdditionalTabVisible(bool on)
     d->m_isAdditionalTabVisible = on;
 }
 
+bool ICodeStylePreferences::additionalTabExist() const
+{
+    return d->m_isAdditionalTabExist;
+}
+
+void ICodeStylePreferences::setAdditionalTabExist(bool on)
+{
+    d->m_isAdditionalTabExist = on;
+}
+
 void ICodeStylePreferences::setTabSettings(const TabSettings &settings)
 {
     if (d->m_tabSettings == settings)

src/plugins/texteditor/icodestylepreferences.h

@@ -44,6 +44,9 @@ public:
     bool isAdditionalTabVisible() const;
     void setIsAdditionalTabVisible(bool on);
 
+    bool additionalTabExist() const;
+    void setAdditionalTabExist(bool on);
+
     void setTabSettings(const TabSettings &settings);
     TabSettings tabSettings() const;
     TabSettings currentTabSettings() const;