Validate the drawing area after the custom painting of the control

This shouldn't be necessary, but it appears some plugins can mess up the painting somehow

See this thread for more details:
http://tortoisesvn.tigris.org/ds/viewMessage.do?dsForumId=4061&dsMessageId=3011957

Based on TortoiseSVN revision 23876

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Don't delete files which contain of one line without a line ending

Only files that have *only* a line ending and the line is empty otherwise are really empty and can be deleted

Based on TortoiseSVN revision 23887

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>