Clang: Rename CodeModelBackEnd in ClangBackEnd

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

tests/unit/unittest/data/complete_extractor_function.cpp

@@ -0,0 +1,22 @@
+void Function();
+template<class T> void TemplateFunction();
+void FunctionWithOptional(int x, char y = 1, int z = 5);
+#define FunctionMacro(X, Y) X + Y
+
+class base {
+    void NotAccessibleFunction();
+};
+class Class : public base {
+    void Method();
+    void MethodWithParameters(int x = 30);
+    __attribute__((annotate("qt_slot"))) void Slot();
+    __attribute__((annotate("qt_signal"))) void Signal();
+    __attribute__ ((deprecated)) void DeprecatedFunction();
+    void NotAvailableFunction() = delete;
+
+public:
+    void function()
+    {
+
+    }
+};