C++: added missing cloning of AnonymousNameId

When instantiate a template with anonymous class/struct/union
AnonymousNameId has to be cloned.

Task-number: QTCREATORBUG-9227

Change-Id: Iedca5e41589e68a94a35cd4387241052c70c50df
Reviewed-by: Sergey Shambir <sergey.shambir.auto@gmail.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/cpptools/cppcompletion_test.cpp

@@ -2015,3 +2015,35 @@ void CppToolsPlugin::test_completion_type_and_using_declaration_data()
             << code << completions;
 
 }
+
+void CppToolsPlugin::test_completion_instantiate_template_with_anonymous_class()
+{
+    TestData data;
+    data.srcText =
+            "template <typename T>\n"
+            "struct S\n"
+            "{\n"
+            "    union { int i; char c; };\n"
+            "};\n"
+            "void fun()\n"
+            "{\n"
+            "   S<int> s;\n"
+            "   @\n"
+            "   // padding so we get the scope right\n"
+            "}\n"
+
+            ;
+    setup(&data);
+
+    Utils::ChangeSet change;
+    QString txt = QLatin1String("s.");
+    change.insert(data.pos, txt);
+    QTextCursor cursor(data.doc);
+    change.apply(&cursor);
+    data.pos += txt.length();
+
+    QStringList completions = getCompletions(data);
+
+    QCOMPARE(completions.size(), 1);
+    QVERIFY(completions.contains(QLatin1String("S")));
+}

src/plugins/cpptools/cpptoolsplugin.h

@@ -126,6 +126,7 @@ private slots:
     void test_completion_QTCREATORBUG9098();
     void test_completion_type_and_using_declaration();
     void test_completion_type_and_using_declaration_data();
+    void test_completion_instantiate_template_with_anonymous_class();
 
     void test_format_pointerdeclaration_in_simpledeclarations();
     void test_format_pointerdeclaration_in_simpledeclarations_data();