CppTools: add multiple refactoring engines support

Make model manager able to select the most functional
refactoring engine from the available ones.

Change-Id: I74031c910706fd694a0a7def022531501f1ea005
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/clangrefactoring/clangqueryprojectsfindfilter.cpp

@@ -127,14 +127,14 @@ void ClangQueryProjectsFindFilter::setProjectParts(const std::vector<CppTools::P
     this->m_projectParts = projectParts;
 }
 
-bool ClangQueryProjectsFindFilter::isUsable() const
+bool ClangQueryProjectsFindFilter::isAvailable() const
 {
-    return m_server.isUsable();
+    return m_server.isAvailable();
 }
 
-void ClangQueryProjectsFindFilter::setUsable(bool isUsable)
+void ClangQueryProjectsFindFilter::setAvailable(bool isAvailable)
 {
-    m_server.setUsable(isUsable);
+    m_server.setAvailable(isAvailable);
 }
 
 SearchHandle *ClangQueryProjectsFindFilter::searchHandleForTestOnly() const

src/plugins/clangrefactoring/clangqueryprojectsfindfilter.h

@@ -66,8 +66,8 @@ public:
 
     void setProjectParts(const std::vector<CppTools::ProjectPart::Ptr> &m_projectParts);
 
-    bool isUsable() const;
-    void setUsable(bool isUsable);
+    bool isAvailable() const;
+    void setAvailable(bool isAvailable);
 
     SearchHandle* searchHandleForTestOnly() const;
 

src/plugins/clangrefactoring/clangrefactoringplugin.cpp

@@ -100,13 +100,15 @@ bool ClangRefactoringPlugin::initialize(const QStringList & /*arguments*/, QStri
 
 void ClangRefactoringPlugin::extensionsInitialized()
 {
-    CppTools::CppModelManager::setRefactoringEngine(&refactoringEngine());
+    CppTools::CppModelManager::addRefactoringEngine(
+                CppTools::RefactoringEngineType::ClangRefactoring, &refactoringEngine());
 }
 
 ExtensionSystem::IPlugin::ShutdownFlag ClangRefactoringPlugin::aboutToShutdown()
 {
     ExtensionSystem::PluginManager::removeObject(&d->qtCreatorfindFilter);
-    CppTools::CppModelManager::setRefactoringEngine(nullptr);
+    CppTools::CppModelManager::removeRefactoringEngine(
+                CppTools::RefactoringEngineType::ClangRefactoring);
     d->refactoringClient.setRefactoringConnectionClient(nullptr);
     d->refactoringClient.setRefactoringEngine(nullptr);
 
@@ -137,7 +139,7 @@ void ClangRefactoringPlugin::connectBackend()
 
 void ClangRefactoringPlugin::backendIsConnected()
 {
-    d->engine.setUsable(true);
+    d->engine.setRefactoringEngineAvailable(true);
 }
 
 } // namespace ClangRefactoring

src/plugins/clangrefactoring/refactoringclient.cpp

@@ -47,7 +47,7 @@ void RefactoringClient::sourceLocationsForRenamingMessage(
                             message.sourceLocations(),
                             message.textDocumentRevision());
 
-    m_refactoringEngine->setUsable(true);
+    m_refactoringEngine->setRefactoringEngineAvailable(true);
 }
 
 void RefactoringClient::sourceRangesAndDiagnosticsForQueryMessage(

src/plugins/clangrefactoring/refactoringengine.cpp

@@ -60,7 +60,7 @@ void RefactoringEngine::startLocalRenaming(const CppTools::CursorInEditor &data,
 {
     using CppTools::ClangCompilerOptionsBuilder;
 
-    setUsable(false);
+    setRefactoringEngineAvailable(false);
 
     m_client.setLocalRenamingCallback(std::move(renameSymbolsCallback));
 
@@ -89,14 +89,14 @@ void RefactoringEngine::startGlobalRenaming(const CppTools::CursorInEditor &)
     // TODO: implement
 }
 
-bool RefactoringEngine::isUsable() const
+bool RefactoringEngine::isRefactoringEngineAvailable() const
 {
-    return m_server.isUsable();
+    return m_server.isAvailable();
 }
 
-void RefactoringEngine::setUsable(bool isUsable)
+void RefactoringEngine::setRefactoringEngineAvailable(bool isAvailable)
 {
-    m_server.setUsable(isUsable);
+    m_server.setAvailable(isAvailable);
 }
 
 } // namespace ClangRefactoring

src/plugins/clangrefactoring/refactoringengine.h

@@ -48,8 +48,8 @@ public:
                             RenameCallback &&renameSymbolsCallback) override;
     void startGlobalRenaming(const CppTools::CursorInEditor &data) override;
 
-    bool isUsable() const override;
-    void setUsable(bool isUsable);
+    bool isRefactoringEngineAvailable() const override;
+    void setRefactoringEngineAvailable(bool isAvailable);
 
     ClangBackEnd::FilePathCachingInterface &filePathCache()
     {