This method removes all groups, group sections, fields and parameters, it resets the DataSources collection so it will contain single DataSource object with name "Main". Resets properties of all nested objects like Layout, Watermark etc. Clears (but does not remove) the fixed sections that all reports have: Detail, Header, Footer, PageHeader, and PageFooter.
Use this method when you want to clear a report and start creating a new one from scratch.
