Clang: Decouple ConnectionClient and ClangCodeModel*

We want to reuse the connection client in other plugins. This is the first
step, the next step is refactoring the IPC mechanismn and move it up to
the IpcServer- and IpcClientInterface.

Change-Id: I6eb6db1e9bc18232c8df350a6303afd2edc68da8
Reviewed-by: Tim Jenssen <tim.jenssen@theqtcompany.com>

src/libs/clangbackendipc/connectionclient.h

@@ -49,7 +49,7 @@ class CMBIPC_EXPORT ConnectionClient : public QObject
     Q_OBJECT
 
 public:
-    ConnectionClient(ClangCodeModelClientInterface *client);
+    ConnectionClient();
     ~ConnectionClient();
 
     void startProcessAndConnectToServerAsynchronously();
@@ -72,14 +72,18 @@ public:
     bool waitForEcho();
     bool waitForConnected();
 
-    ClangCodeModelServerProxy &serverProxy();
-
     QProcess *processForTestOnly() const;
 
 signals:
     void connectedToLocalSocket();
     void processFinished();
 
+protected:
+    QIODevice *ioDevice();
+
+    virtual void sendEndCommand() = 0;
+    virtual void resetCounter() = 0;
+
 private:
     std::unique_ptr<QProcess> startProcess();
     void finishProcess(std::unique_ptr<QProcess> &&process);
@@ -107,14 +111,13 @@ private:
 private:
     mutable std::unique_ptr<QProcess> process_;
     QLocalSocket localSocket;
-    ClangCodeModelServerProxy serverProxy_;
     QTimer processAliveTimer;
     QString processPath_;
     bool isAliveTimerResetted = false;
     bool processIsStarting = false;
 
-    LinePrefixer stdErrPrefixer;
-    LinePrefixer stdOutPrefixer;
+    LinePrefixer stdErrPrefixer = QByteArrayLiteral("clangbackend.stderr: ");
+    LinePrefixer stdOutPrefixer = QByteArrayLiteral("clangbackend.stdout: ");
 };
 
 } // namespace ClangBackEnd