DebugTools: reduce test precision for Emscripten.
DebugTools: reduce test precision for Emscripten.

Again, works w/o problem with -O2, this is just in case of -O1.

MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum