PchManager: Split pch tasks in project and system pch tasks

Like you can see in the task numbers this patch is touching many different
areas. So I will only touch the main parts. It is using a clang action
instead of an extra process which will be enabling the handling of
generated files in PCHs. The flags from the project part are now not
anymore transformed in a command line but they are saved in the container
semantically aware so that they can later be merged. Most of this patch is
simply polishing of other patches.

Task-number: QTCREATORBUG-21346
Task-number: QTCREATORBUG-21380
Task-number: QTCREATORBUG-21382
Task-number: QTCREATORBUG-21383
Task-number: QTCREATORBUG-21693
Task-number: QTCREATORBUG-21778
Change-Id: I9b0c02d8149b554254e819448fbc61eeaa5b7494
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/libs/clangsupport/projectpartcontainer.cpp

@@ -0,0 +1,41 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 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.
+**
+****************************************************************************/
+
+#include "projectpartcontainer.h"
+
+namespace ClangBackEnd {
+
+QDebug operator<<(QDebug debug, const ProjectPartContainer &container)
+{
+    debug.nospace() << "ProjectPartContainer("
+                    << container.projectPartId << ","
+                    << container.toolChainArguments << ", "
+                    << container.headerPathIds << ", "
+                    << container.sourcePathIds
+                    << ")";
+
+    return debug;
+}
+} // namespace ClangBackEnd