angular#62630 made it so that all ARIA
property bindings would write to their corresponding attribute instead.
The primary motivation for this change was to ensure that ARIA
attributes were always rendered correctly on the server, where the
emulated DOM may not correctly reflect ARIA properties as attributes.
Furthermore, this change added support for binding to ARIA attributes
using the property binding syntax (e.g. `[aria-label]`).

Unfortunately, angular#62630 relied on
the incorrect assumptions that an ARIA property name could be converted
to its attribute name (without hardcoding the conversion), and that the
value of an ARIA property matched its corresponding attribute. For
example, the `ariaLabelledByElements` property's value is an array of
DOM elements, while the corresponding `aria-labelledby` attribute's
value is a string containing the IDs of the DOM elements.

This partially reverts angular#62630 so
that only property bindings with ARIA attribute names (begin with
`aria-`) are converted to attribute bindings.

* `[ariaLabel]` will revert to binding to the `ariaLabel` property.
* `[aria-label]` will continue binding to the `aria-label` attribute.

Note the only difference between `[aria-label]` and `[attr.aria-label]`
is that the former will attempt to bind to inputs of the same name while
the latter will not.