Modify TestApps to use mandatory source URI

Modifies the TestApps to use the new mandatory
DownloadRequest#Builder constructor.

Test: Manual, Run TestApps
Bug: 67640102
Merged-In: If92c54d22cfc8caf9d0f9caeff6f2a6e0747072f
Change-Id: I3ab21db90f3b998c8ef1d068e2410d6afe5982a7
2 files changed