Add tests for creating bulk and non-bulk items that we know will succeed;
I did this change to test for #1397, but it's a reasonable way to do more
testing in fops.
Don't divide by 0 if the file is 0 bytes.
No chunks exist before an item is inserted into the tree. Initialize the
data source statistics and then aggregate into those values in all
cases, instead of assigning the first chunk's statistics into the data
source statistics.
whitespace