Page: Consult $.mobile.keepNative during the execution of keepNativeSelector() to ensure that modifications made during mobileinit are taken into consideration. Fixes #6478.
Page: Removing option keepNative because it was never documented and disallowing the simultaneous modification of the deprecated prototype option and the new global setting ($.mobile.keepNative). $.mobile.keepNative, if modified, takes precedence over $.mobile.page.prototype.options.keepNativeDefault.