Code pointers for fdo#43650

Hi,

I would like to work on Bug #43650 [1].

The bug is about disabling the tooltip showing Title/Page number when 
scrolling in Writer. But it should only be disabled when scrolling with 
the mouse wheel, not when dragging the scroll bar. From this Apache 
patch [2] I can see where the tool tip is drawn.

What I want to do different than Apache does, is that whether the tool 
tip is shown or not, should not be based on a configuration setting, but 
on whether one is using the mouse wheel.

Can someone please have a look at it and give me a code pointer for that?

Thanks
Samuel

[1] https://bugs.freedesktop.org/show_bug.cgi?id=43650
[2] http://svn.apache.org/viewvc?view=revision&revision=1419993