ClangCodeModel: Switch off clangd persistently

... after failed machine suitability check.

Fixes: QTCREATORBUG-28441
Change-Id: Ic0fb956168204d8023ff96f92ae3fcd7cea8b0e9
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -127,7 +127,7 @@ static void checkSystemForClangdSuitability()
     if (ClangdSettings::hardwareFulfillsRequirements())
         return;
 
-    ClangdSettings::setUseClangd(false);
+    ClangdSettings::setUseClangdAndSave(false);
     const QString warnStr = ClangModelManagerSupport::tr("The use of clangd for the C/C++ "
             "code model was disabled, because it is likely that its memory requirements "
             "would be higher than what your system can handle.");
@@ -148,7 +148,7 @@ static void checkSystemForClangdSuitability()
         return label;
     });
     info.addCustomButton(ClangModelManagerSupport::tr("Enable Anyway"), [clangdWarningSetting] {
-        ClangdSettings::setUseClangd(true);
+        ClangdSettings::setUseClangdAndSave(true);
         Core::ICore::infoBar()->removeInfo(clangdWarningSetting);
     });
     Core::ICore::infoBar()->addInfo(info);

src/plugins/cppeditor/cppcodemodelsettings.cpp

@@ -218,6 +218,12 @@ bool ClangdSettings::useClangd() const
 
 void ClangdSettings::setUseClangd(bool use) { instance().m_data.useClangd = use; }
 
+void ClangdSettings::setUseClangdAndSave(bool use)
+{
+    setUseClangd(use);
+    instance().saveSettings();
+}
+
 bool ClangdSettings::hardwareFulfillsRequirements()
 {
     instance().m_data.haveCheckedHardwareReqirements = true;

src/plugins/cppeditor/cppcodemodelsettings.h

@@ -126,6 +126,7 @@ public:
     static ClangdSettings &instance();
     bool useClangd() const;
     static void setUseClangd(bool use);
+    static void setUseClangdAndSave(bool use);
 
     static bool hardwareFulfillsRequirements();
     static bool haveCheckedHardwareRequirements();