scintilla scrollbars: ensure real and fake scrollbars stay in sync
* otherwise we get two scrollbars when minimap is visible (in real case)

(integrated from komodo (trunk) change 81116 by toddw)

git-svn-id: http://svn.openkomodo.com/repos/openkomodo/trunk@13319 b87d16e7-d29f-4ee1-b5ec-817d645d335f