[Extra zoom mode] Adopt list view controller UI for select menus

[Extra zoom mode] Adopt list view controller UI for select menus
https://bugs.webkit.org/show_bug.cgi?id=183944
<rdar://problem/38799062>

Reviewed by Andy Estes.

Rename WKSelectMenuViewController to WKSelectMenuListViewController, and also rename the relevant
WebKitAdditions harness files. See corresponding changes for more details.

* UIProcess/WKSelectMenuListViewController.h: Renamed from Source/WebKit/UIProcess/ios/forms/WKSelectMenuViewController.h.
* UIProcess/WKSelectMenuListViewController.mm: Renamed from Source/WebKit/UIProcess/ios/forms/WKSelectMenuViewController.mm.
* UIProcess/ios/WKContentViewInteraction.h:
* UIProcess/ios/WKContentViewInteraction.mm:
(-[WKContentView presentSelectMenuViewController:]):
(-[WKContentView dismissSelectMenuViewController:]):
(-[WKContentView selectMenu:didSelectItemAtIndex:]):
(-[WKContentView numberOfItemsInSelectMenu:]):
(-[WKContentView selectMenu:displayTextForItemAtIndex:]):
(-[WKContentView selectMenu:didCheckItemAtIndex:checked:]):
(-[WKContentView selectMenuUsesMultipleSelection:]):
(-[WKContentView selectMenu:hasSelectedOptionAtIndex:]):
(-[WKContentView _wheelChangedWithEvent:]):

Overriding wheel events and re-dispatching them is no longer needed after r229437, so we can just remove special
handling for select menus here.

(-[WKContentView didCancelSelectionInSelectMenu:]): Deleted.
(-[WKContentView selectMenuSupportsMultipleSelection:]): Deleted.
(-[WKContentView selectMenu:hasCheckedOptionAtIndex:]): Deleted.
(-[WKContentView startingIndexForSelectMenu:]): Deleted.

The starting index for a select menu is no longer relevant when using list view controllers for input, so we can
just remove this delegate hook altogether.

* WebKit.xcodeproj/project.pbxproj:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@229916 268f45cc-cd09-0410-ab3c-d52691b4dbfc