CppEditor: add more sections (protected, ...) for declaration (refactoring)

You can write definition of function, type Alt+Enter, as usual,
and select not only public but also other possible sections
like private, public slots and so on.

Change-Id: I2faefc3833c6f05c9e2e5a2a41328bcdbe17ba14
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/texteditor/basetexteditor.cpp

@@ -6210,7 +6210,7 @@ int BaseTextEditorWidget::lineNumberDigits() const
 
 bool BaseTextEditorWidget::selectionVisible(int blockNumber) const
 {
-    Q_UNUSED(blockNumber)
+    Q_UNUSED(blockNumber);
     return true;
 }