I'm writing a CL to resolve  issue 783418 , and I was surprised to realize that the media/ui java tests [1] aren't compiled with the O SDK, but with the N_MR1 SDK. My evidence is that `Build.VERSION_CODES.O` isn't defined (but N_MR1 is).

Why do these tests use a different SDK than the rest of chromium? Is there a reason this shouldn't move up to the O SDK?

Possible duplicate of issue 729029 (the meaning of that issue wasn't clear to me).

[1] https://cs.chromium.org/chromium/src/chrome/android/junit/src/org/chromium/chrome/browser/media/ui/MediaNotificationFaviconTest.java?l=87