The pptx chart data source been saved in pptx file package as a separate
file in xlsx format or binary format, and zipped with pptx file together. But
there is data cache saved with chart description in chart.xml.
After this part of implementation, the chart could be imported and will
show the same with originally in MS Office. For the basic scenario, the pptx
chart can be imported correctly in Aoo.
Detail is in the attachment.2012-09-05 tanmgeng
