Switching between declaration/definition used to also work if the cursor was e.g. on the return type of the method. In 2.8, if the cursor is before the method name, it jumps to the method before that method. E.g. when pressing shift+F2 in the situation of the screenshot, it goes to the declaration of SplitterOrView::mousePressEvent instead of SplitterOrView::findFirstView

I haven't checked 2.7 yet.