QDeclarativeTextInput::mousePressEvent() doesn't call QInputContext::mouseHandler()

When investigating an issue with using the QML text input element with a custom InputContext, I find that the InputContext's mouseHandler() is not called.

The user story concerned word suggestions :

1) while typing a word, the current 'word' is underlined
2) tapping on the underlined 'word' results in a list of suggestions in
a pop-up dialog

This doesn't happen and is seems to be that the
QDeclarativeTextInput::mousePressEvent() method doesn't call the
mouseHandler() in the input context, which is what happens in
widgets/qlineedit_p.cpp for example.

I have worked around the issue by adding a MouseArea to the element and invoking a method in a C++ class to forward on the mouse press event. This works but causes other issues.