3f0ad9d4f2
Fixes issue #24813. Doesn't add a second codec. The codec is unimportant, only the BASE64 and BASE64URL constants need to be public anyway. BUG= http://dartbug.com/24813 R=floitsch@google.com, nweiz@google.com Review URL: https://codereview.chromium.org/1858113003.