Use REST API to create new product can't save product custom options

[xiaogang87]

Steps to reproduce

1. POST a new product with custom options to "/rest/V1/products"

Expected result

1. a new product with custom options

Actual result

1. a new product without custom options
2. After I debug it, I found wrong code may exist in the save function of "\vendor\magento\module-catalog\Model\ProductRepository.php".

In line 565, get a null $productOptions
In line 585, set the right options to $product
In line 603, set the null $productOptions as product options to the $product

[piotrekkaminski]

Internal issue MAGETWO-53565

[aohorodnyk]

I cannot reproduce issue in latest mainline and 2.0 branch, so I am closing this issue, as fixed. Feel free to reopen issue if we missed anything.