[[TypedArrayConstructorName]] no longer needed

[allenwb]

The [[TypedArrayConstructorName]] internal slot of TypedArray constructors is no longer needed now that the secondary prototype walk has been eliminated by the changes made in the 2015-12-20 draft.

[[TypedArrayConstructorName]] was formally needed because each of the individual TypedArray constructors super called to %TypedArray% and that shared constructor algorithm needed a way to identify the element type of the instance being constructed.

However, with the recent changes, each TypedArray constructor is a distinct function. Hence, the desired element type can be literally coded within each constructor.

Here is sketch of the changes that need to be make:

• In 22.2.4.1
• add a new step after step 1: Let constructorName be the String value of the Constructor Name value specified in Table 50 for this TypedArray constructor.
• Change the first argument of the call to AllocateTypedArray to be constructorName instead of TypedArray.[[TypedArrayConstructorName]].
• Make similar changes in 22.2.4.2, 22.2.4.3, 22.2.4.5
• In 22.2.5 delete the paragraph that defines the [[TypedArrayConstructorName]] internal slot.

[ljharb]

No objections or concerns from me :-) but just in case, I wanted to point to my which-typed-array module whose behavior indirectly depends on the [[TypedArrayName]] internal slot of instances, which are currently populated via the [[TypedArrayConstructorName]] mechanism (and will remain correctly populated in each AllocateTypedArray call with @allenwb's suggested changes).