Added a version of +[NSURL _web_URLWithWTFString:relativeToURL:] that doesn’t take a base URL and switched all callers to it.
https://bugs.webkit.org/show_bug.cgi?id=125040

Reviewed by Sam Weinig.

* Shared/Cocoa/WKNSURLExtras.h: Declared new method.
* Shared/Cocoa/WKNSURLExtras.mm:
(urlWithWTFString): Added helper function.
(+[NSURL _web_URLWithWTFString:]): Added.
(+[NSURL _web_URLWithWTFString:relativeToURL:]): Changed to use helper function.
* UIProcess/API/Cocoa/WKBackForwardListItem.mm:
(-[WKBackForwardListItem URL]): Changed to call new method.
(-[WKBackForwardListItem originalURL]): Ditto.
* UIProcess/API/Cocoa/WKBrowsingContextController.mm:
(-[WKBrowsingContextController activeURL]): Ditto.
(-[WKBrowsingContextController provisionalURL]): Ditto.
(-[WKBrowsingContextController committedURL]): Ditto.
(-[WKBrowsingContextController unreachableURL]): Ditto.
(setUpPagePolicyClient): Ditto.
* UIProcess/API/Cocoa/WKNavigationData.mm:
(-[WKNavigationData destinationURL]): Ditto.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@159895 268f45cc-cd09-0410-ab3c-d52691b4dbfc