ClangTools: Split generic part from static analyzer tool

To reuse it for other clang-based tools.

Change-Id: I6c0d8e9eee543fa08faf3bf93c9fac33e43c6820
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/clangtools/clangtoolsdiagnostic.cpp

@@ -0,0 +1,47 @@
+/****************************************************************************
+**
+** 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 "clangtoolsdiagnostic.h"
+
+namespace ClangTools {
+namespace Internal {
+
+ExplainingStep::ExplainingStep()
+    : depth(0)
+{
+}
+
+bool ExplainingStep::isValid() const
+{
+    return location.isValid() && !ranges.isEmpty() && !message.isEmpty();
+}
+
+bool Diagnostic::isValid() const
+{
+    return !description.isEmpty();
+}
+
+} // namespace Internal
+} // namespace ClangTools