Comment 38 for bug 604635

Android has a nice (conceptual) solution for this, which is the notion of a "wake lock" that prevents the display from turning off (~screensaver). What's nice about this compared to a binary on/off API is that it composes well across multiple callers, and is extensible to locking other kinds of power-saving mechanisms (like low-power CPU idle). I would be in favor of an API like that, but I'm not sure what a good DOM-y solution would look like.