Fix a race spotted by Nils:  We have to hold a ref to the
busyobj if we want to examine it in any detail.

Hold that ref over all of V1D_Deliver() (different from Nils
patch) to make sure we have a consistent view on streaming
vs. no streaming throughout.

Also use the bo to clean up a hack related to ESI includes.

Diagnosed by:	Nils Goroll