C++: Revert lookup to 3.4.2

...which was least buggy.

The bugs fixed by the changes we revert here (highlighting/completion
for code involving templates) were minor compared to ones we currently
have. Those bugs will be addressed by the clang code model anyway.

Relevant commits were collected via:

  $ cd ${QTC}/src/libs/cplusplus
  $ git log \
   --no-merges \
   --format=oneline \
   v3.4.2..HEAD \
   -- LookupContext.* ResolveExpression.* TypeResolver.* TypeOfExpression.* \
      ../../plugins/cpptools/cppcompletion_test.cpp

From this list the following were skipped due to irrelevance:

  88c5b47e53 # CppTools: Minor cleanup in completion tests
  e5255a1f5c # CppTools: Add a test for ObjC not replacing dot with arrow
  5b12c8d63a # CppTools: Support ObjC in member access operator tests
  9fef4fb9ca # CPlusPlus: Fix warnings about overriding visit(...) methods

There were only minor conflicts while reverting those.

This changes touches so many files because there were quite some
cleanups and renames after the 3.4.2 release.

Task-number: QTCREATORBUG-14889
Task-number: QTCREATORBUG-15211
Task-number: QTCREATORBUG-15213
Task-number: QTCREATORBUG-15257
Task-number: QTCREATORBUG-15264
Task-number: QTCREATORBUG-15291
Task-number: QTCREATORBUG-15329
Change-Id: I01f759f8f35ecb4228928a4f22086e279c1a5435
Reviewed-by: Marco Bubke <marco.bubke@theqtcompany.com>

src/libs/cplusplus/DeprecatedGenTemplateInstance.h

@@ -0,0 +1,63 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://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 http://www.qt.io/terms-conditions.  For further information
+** use the contact form at http://www.qt.io/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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file.  Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, The Qt Company gives you certain additional
+** rights.  These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef CPLUSPLUS_DEPRECATEDGENTEMPLATEINSTANCE_H
+#define CPLUSPLUS_DEPRECATEDGENTEMPLATEINSTANCE_H
+
+#include <cplusplus/TypeVisitor.h>
+#include <cplusplus/NameVisitor.h>
+#include <cplusplus/FullySpecifiedType.h>
+
+#include <QList>
+#include <QPair>
+#include <QSharedPointer>
+
+namespace CPlusPlus {
+
+class CPLUSPLUS_EXPORT DeprecatedGenTemplateInstance
+{
+public:
+    typedef QList< QPair<const Identifier *, FullySpecifiedType> > Substitution;
+
+public:
+    static FullySpecifiedType instantiate(const Name *className, Symbol *candidate, QSharedPointer<Control> control);
+
+private:
+    DeprecatedGenTemplateInstance(QSharedPointer<Control> control, const Substitution &substitution);
+    FullySpecifiedType gen(Symbol *symbol);
+
+private:
+    QSharedPointer<Control> _control;
+    const Substitution _substitution;
+};
+
+} // namespace CPlusPlus
+
+#endif // CPLUSPLUS_DEPRECATEDGENTEMPLATEINSTANCE_H