Debugger: Fix Symbian.

...which subclasses DebuggerRunner and does not call
DebuggerPlugin::startDebugger(), which connects the
engine, leading to strange malfunctions. Move functionality
to DebuggerRunner::start() to make it self-contained.
Add object names to engines for easier debugging.

Reviewed-by: hjk

src/plugins/debugger/gdb/gdbengine.cpp

@@ -178,6 +178,7 @@ static QByteArray parsePlainConsoleStream(const GdbResponse &response)
 GdbEngine::GdbEngine(const DebuggerStartParameters &startParameters)
   : DebuggerEngine(startParameters)
 {
+    setObjectName(QLatin1String("GdbEngine"));
     qRegisterMetaType<WatchData>("WatchData");
 
     m_commandTimer = new QTimer(this);