PluginManager: Clean up

* Remove unused testDataDirectory()
* Move startTests() to PluginManagerPrivate

Change-Id: I3ad582a7ea35c8f08d1455ea3536baed88ecb2ad
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/libs/extensionsystem/pluginmanager.h

@@ -145,7 +145,6 @@ public:
     static QString serializedArguments();
 
     static bool testRunRequested();
-    static QString testDataDirectory();
 
     static void profilingReport(const char *what, const PluginSpec *spec = 0);
 
@@ -162,8 +161,6 @@ public slots:
     void remoteArguments(const QString &serializedArguments, QObject *socket);
     void shutdown();
 
-private slots:
-    void startTests();
     friend class Internal::PluginManagerPrivate;
 };