[Extra zoom mode] Adopt list view controller UI for numeric input types

[Extra zoom mode] Adopt list view controller UI for numeric input types
https://bugs.webkit.org/show_bug.cgi?id=184184
<rdar://problem/37238916>

Reviewed by Timothy Hatcher.

Source/WebCore:

Add a localized string for the OK button shown on number pads in extra zoomed form controls.

* English.lproj/Localizable.strings:
* platform/LocalizedStrings.cpp:
(WebCore::numberPadOKButtonTitle):
* platform/LocalizedStrings.h:

Source/WebKit:

Remove existing logic for presenting a number pad view controller, since number pads will now be handled as a
special case of general text form controls in extra zoom mode.

* UIProcess/ios/WKContentViewInteraction.h:
* UIProcess/ios/WKContentViewInteraction.mm:
(-[WKContentView presentViewControllerForCurrentAssistedNode]):
(-[WKContentView dismissAllInputViewControllers]):
(-[WKContentView _wheelChangedWithEvent:]):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@230122 268f45cc-cd09-0410-ab3c-d52691b4dbfc