1. Added an AccessibilityDelegate class in View which can be set by
a client that wants to cutomize accessibility behavior via
composition as opposed to inheritance. Insead overriding a new method in
View thus being bound to the API version that introduced this
method a developer can conditionally inject the accessibility
customization if the platform API version is heigh enough. The
developer will have to override the method of interest of the
delegate. The default implementation of the delegate methods is
the same as that of View in the case that there is no delegate
set. If a delegate is set calling an accessibility related method
on View will be handed off to the corresponsing method of the
delegate.
bug:5259555
Change-Id: I00e750e22e5e7164a1b571cb3d12ecaf4ab93db4
031d9c1389