Moved testing code to the bottom of the file. The next CL should be the removal of the DownloadSet. Also fixed b/15003801, so that the test will not fail. Change-Id: Ie8320782d6b292d5a367af95d7c58d70a4213ead
Also a bit of cleanup around log tags and DownloadRequest. Change-Id: I33221f099ed691e5258e1741cf0a63381404f520