[webidl] 'Reject' definition. (#73)

In https://heycam.github.io/webidl/#named-properties-object-defineownproperty and https://heycam.github.io/webidl/#defineownproperty
The term "Reject" is referring to a non-existent section.
Ex: 
> ...MUST behave as follows when called with object O and property name P. The term “Reject” is used as defined in section @@ @@.
>
>1.   Reject.
>

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Reply to this email directly or view it on GitHub:
https://github.com/heycam/webidl/issues/73