VcsBase: Create common base diff editor controller

Reuse it in subversion and git plugins.
It makes subversion diff more asynchronous than before.
Make VcsBase plugin dependand on DiffEditor plugin.

Change-Id: Iafea2941b890a95a269362e022af2dc03cdea550
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

src/plugins/vcsbase/vcsbasediffeditorcontroller.h

@@ -0,0 +1,62 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include "vcsbase_global.h"
+#include <diffeditor/diffeditorcontroller.h>
+
+namespace Core { class IDocument; }
+
+namespace VcsBase {
+
+class VcsBaseClientImpl;
+class VcsBaseDiffEditorControllerPrivate;
+
+class VCSBASE_EXPORT VcsBaseDiffEditorController : public DiffEditor::DiffEditorController
+{
+    Q_OBJECT
+
+public:
+    VcsBaseDiffEditorController(Core::IDocument *document,
+                                VcsBaseClientImpl *client,
+                                const QString &workingDirectory);
+    ~VcsBaseDiffEditorController();
+
+protected:
+    void runCommand(const QList<QStringList> &args, unsigned flags, QTextCodec *codec = nullptr);
+    virtual void processCommandOutput(const QString &output);
+
+    VcsBaseClientImpl *client() const;
+    QString workingDirectory() const;
+    void setStartupFile(const QString &startupFile);
+    QString startupFile() const;
+
+private:
+    friend class VcsBaseDiffEditorControllerPrivate;
+    VcsBaseDiffEditorControllerPrivate *d;
+};
+
+} //namespace VcsBase