QmlJS: Editor: Explicitly 'Open in QmlJSEditor' opens ui.qml file in Designer

Steps to reproduce:

• create Qt Quick Application from template (make sure you have ui.qml file)
• on the 'Projects' navigation tree trigger 'Open With' -> 'QMLJS Editor' on the node with the MainForm.ui.qml

Current result:

• QC opens the file inside Quick Designer
• you have to switch back to Edit mode to manually edit this file (or use the now embedded editor inside the Designer)

Expected result:

• QC should open the file inside QmlJS Editor..