CppTools: Use consistent sorting in the two outlines

Use case-sensitive sorting in the side bar outline, just like in
the editor outline.

Fixes: QTCREATORBUG-12714
Change-Id: I9d8243c61fcceb6e3d7b55e3b27fa5d20accccea
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/cpptools/cppeditoroutline.cpp

@@ -104,7 +104,6 @@ CppEditorOutline::CppEditorOutline(TextEditor::TextEditorWidget *editorWidget)
     else
         m_proxyModel->sort(-1, Qt::AscendingOrder); // don't sort yet, but set column for sortedOutline()
     m_proxyModel->setDynamicSortFilter(true);
-    m_proxyModel->setSortCaseSensitivity(Qt::CaseInsensitive);
 
     // Set up combo box
     m_combo->setModel(m_proxyModel);