Need help on Easy Hack 42788..

I ve been working on my first hack(though i ve not assigned it to
myself) : Easy
Hack 42788 <https://bugs.freedesktop.org/show_bug.cgi?id=42788> -
FORMATTING - Numbering/ordered list results in misaligned text after a
certain level: default indent does not match with the width of
numbers/bullets

All i could do was change one line of code in sw/source/core/doc/number.cxx
line 432: pFmt->SetListtabPos( cIndentAt[ n ] + 1440/5 );

But the thing is a rough code pointer( by Björn Michaelsen ) was already
given.
This line changes the default value to +.2 inch.. The bug was, when the
space between the BulletChar and the input text is null, an additional tab
was getting added. This made the text look ugly.. Even after the addition
of the above line the bug persists, but the appearance of the bug has been
delayed, ie previously after 100( ie. 3 bullet char) the tab was getting
added, but now after 10000( 6 bullet char) the tab will get added.

I ve worked on this hack for a very long time, navigating within methods to
understand parts of code, using gdb to watch the change of variables to
track down the problem.
I really want to know where the default value is getting incremented. Can
some body guide me so I can actually complete this hack.?
Thank you.

Attachment: After Change.png
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Attachment: Before change.png
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