Updating testing XhrIo to allow for Blob response, which is supported by XhrIo itself. RELNOTES: n/a
Updating testing XhrIo to allow for Blob response, which is supported by XhrIo itself.
RELNOTES: n/a

PiperOrigin-RevId: 438967407
Change-Id: Iaa553e3fe42f32054d8da1c12809cc3aef0a0aa8

google/closure-library,google/closure-library,google/closure-library,google/closure-library,google/closure-library