I worry that adding this functionality to decorators will be brittle.

You can always define a ShouldDisable method, which takes a possible_browser. I'm kind of thinking that maybe the thing we should do here is simply expose GetProp through android_platform, for this kind of tools/perf-side wrangling.

Chatted offline with Ned and Kari; actually we can add this to decorators using GetDeviceType. I'll investigate this later.