Unreviewed test fix after r226224.

Unreviewed test fix after r226224.
<rdar://problem/36185975>

Pasteboard data is more than a dictionary. We have to whitelist NSString
and NSArray as well. Change method name to reflect that we take a whitelist
of classes that are allowed to be unarchived in the call.
Source/WebCore:

* platform/ios/PlatformPasteboardIOS.mm:
(WebCore::PlatformPasteboard::write): Use revised method.
(WebCore::PlatformPasteboard::typesSafeForDOMToReadAndWrite const): Ditto.

Source/WebCore/PAL:

* pal/spi/cocoa/NSKeyedArchiverSPI.h:
(unarchivedObjectOfClassesFromData):
(unarchivedObjectOfClassFromData): Deleted.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@226248 268f45cc-cd09-0410-ab3c-d52691b4dbfc