The spec doesn't tell us the exact value to use, but a minumum & maximum
range of supported values. Just to be consistent with another browser,
we follow the values that firefox appears to support from testing the
interface on my machine.
This function will be used in the AudioBuffer constructor, but is
defined in the spec as part of BaseAudioContext.
This commit introduces a WEB_SET_PROTOTYPE_FOR_INTERFACE macro that
caches the interface name in a local static FlyString. This means that
we only pay for FlyString-from-literal lookup once per browser lifetime
instead of every time the interface is instantiated.