fix defineProperty() proxy hook for array length

[farwayer]

Summary

Fixes #1910

internalSetter() should be called in JSObject::putNamedWithReceiver_RJS() only if target object is the same as receiver.
The lack of check resulted in the Proxy::defineOwnProperty() call being skipped for the array's internal length property. This, in turn, resulted in the Proxy's defineProperty() hook being ignored.

Correct flow by spec for push (and one level proxying Proxy -> Array):
...
Array.prototype.push
// item operations
[[Proxy::Set]](length)
// calling proxy set() hook or...
[[Ordinary::Set]](length, receiver=Proxy)
OrdinarySet(length, receiver=Proxy)
OrdinarySetWithOwnDescriptor(length, receiver=Proxy)
[[Proxy::DefineOwnProperty]](length)
// calling proxy defineProperty() hook or...
[[Array::DefineOwnProperty]](length)
[[Array::ArraySetLength]]
OrdinaryDefineOwnProperty(length)
...

Test Plan

let log = (...args) => typeof print === 'undefined' ? console.log(JSON.stringify(args)) : print(JSON.stringify(args))

let arr = new Proxy([], {
	defineProperty(target, property, attributes) {
		log('define', target, property, attributes)
		return Reflect.defineProperty(target, property, attributes)
	},
	deleteProperty(target, p) {
		log('del', target, p)
		return Reflect.deleteProperty(target, p)
	},
})

log('push')
arr.push('a')
log('push')
arr.push('b')
log('push')
arr.push('c')
log('pop')
arr.pop()
log('shift')
arr.shift()
log('length=')
arr.length = 1

Result before fix:

["push"]
["define",[],"0",{"value":"a","writable":true,"enumerable":true,"configurable":true}]
["push"]
["define",["a"],"1",{"value":"b","writable":true,"enumerable":true,"configurable":true}]
["push"]
["define",["a","b"],"2",{"value":"c","writable":true,"enumerable":true,"configurable":true}]
["pop"]
["del",["a","b","c"],"2"]
["shift"]
["define",["a","b"],"0",{"value":"b"}]
["del",["b","b"],"1"]
["length="]

After:

["push"]
["define",[],"0",{"value":"a","writable":true,"enumerable":true,"configurable":true}]
["define",["a"],"length",{"value":1}]
["push"]
["define",["a"],"1",{"value":"b","writable":true,"enumerable":true,"configurable":true}]
["define",["a","b"],"length",{"value":2}]
["push"]
["define",["a","b"],"2",{"value":"c","writable":true,"enumerable":true,"configurable":true}]
["define",["a","b","c"],"length",{"value":3}]
["pop"]
["del",["a","b","c"],"2"]
["define",["a","b",null],"length",{"value":2}]
["shift"]
["define",["a","b"],"0",{"value":"b"}]
["del",["b","b"],"1"]
["define",["b",null],"length",{"value":1}]
["length="]
["define",["b"],"length",{"value":1}]