Clang: Rename CodeModelBackEnd in ClangBackEnd

Change-Id: I13e8a458634110456375956d4d4da7239c86957f
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

tests/unit/unittest/data/complete_extractor_variable.cpp

@@ -0,0 +1,36 @@
+void function(int Parameter)
+{
+    int Var = 0;
+
+}
+
+void function2()
+{
+    int Var = 0;
+    auto Lambda = [&Var]()
+    {
+
+    };
+}
+
+class Class {
+    int Field;
+
+    void function() {
+
+    }
+};
+
+template <int NonTypeTemplateParameter>
+void function3() {}
+
+#define MacroDefinition
+
+
+void function4()
+{
+#ifdef ArgumentDefinition
+    int ArgumentDefinitionVariable;
+#endif
+
+}