Fix mismatched ProxyTraps signature #401

Job	Run time
Integrity	18s
mac (--features debugmozjs)	16m 22s
mac	18m 39s
linux (--features debugmozjs)	10m 58s
linux	14m 5s
windows (--features debugmozjs)	16m 32s
windows (--features debugmozjs, aarch64-uwp-windows-msvc)	17m 47s
windows (--features debugmozjs, x86_64-uwp-windows-msvc)	20m 15s
windows	14m 25s
windows (aarch64-uwp-windows-msvc)	14m 55s
windows (x86_64-uwp-windows-msvc)	14m 26s
Result	1s
	2h 38m 43s

Provide feedback