QmlProfiler: Add EngineControl

With EngineControl multiple QQuickViews can be profiled in one
profiler if they're all running in the same thread. As the QML
engines are never run in parallel then this results in useful
data.

Change-Id: I83a34fb81fd466c5cac838b096c1b1f322ded882
Reviewed-by: Kai Koehne <kai.koehne@digia.com>

src/libs/qmldebug/qmlenginecontrolclient.h

@@ -0,0 +1,81 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QMLENGINECONTROLCLIENT_H
+#define QMLENGINECONTROLCLIENT_H
+
+#include "qmldebugclient.h"
+
+namespace QmlDebug {
+
+class QMLDEBUG_EXPORT QmlEngineControlClient : public QmlDebugClient
+{
+    Q_OBJECT
+public:
+    explicit QmlEngineControlClient(QmlDebugConnection *client);
+
+    enum MessageType {
+        EngineAboutToBeAdded,
+        EngineAdded,
+        EngineAboutToBeRemoved,
+        EngineRemoved
+    };
+
+    enum CommandType {
+        StartWaitingEngine,
+        StopWaitingEngine,
+        InvalidCommand
+    };
+
+
+    void blockEngine(int engineId);
+    void releaseEngine(int engineId);
+
+signals:
+    void engineAboutToBeAdded(int engineId, const QString &name);
+    void engineAdded(int engineId, const QString &name);
+    void engineAboutToBeRemoved(int engineId, const QString &name);
+    void engineRemoved(int engineId, const QString &name);
+
+protected:
+    void messageReceived(const QByteArray &);
+    void sendMessage(CommandType command, int engineId);
+
+    struct EngineState {
+        EngineState(CommandType command = InvalidCommand) : releaseCommand(command), blockers(0) {}
+        CommandType releaseCommand;
+        int blockers;
+    };
+
+    QMap<int, EngineState> m_blockedEngines;
+};
+
+}
+
+#endif // QMLENGINECONTROLCLIENT_H