Forgot to publish the new accessor as WK2 API.
Created attachment 78018 [details]
Attachment 78018 [details] did not pass style-queue:
Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'WebKit2/ChangeLog', u'WebKit2/UIProcess/API/C/WKPage.cpp', u'WebKit2/UIProcess/API/C/WKPage.h']" exit_code: 1
WebKit2/UIProcess/API/C/WKPage.h:271: The parameter name "page" adds no information, so it should be removed. [readability/parameter_name] 
Total errors found: 1 in 3 files
If any of these errors are false positives, please file a bug against check-webkit-style.
Filed 51938 against check-webkit-style.