8024255: When a keyword is used as object property name, the property can not be deleted
Reviewed-by: jlaskey, lagergren
x instanceof f: true
x instanceof b: true
y instanceof f: true
y instanceof b: true
Changing prototype
x instanceof f: false
x instanceof b: false
y instanceof f: false
y instanceof b: false
Bound function prototype
f.hasOwnProperty('prototype'): true
b.hasOwnProperty('prototype'): false