Gets the URL that has a cert error and carrys it in SslError.

b/2689122 SSL error shows the wrong page when triggered by an image/javascript in the page.
This change receives the URL which has a cert error from webkit and carrys it in SslError.
so the Browser app can show the URL in the dialog boxes. Related CLs are:
   webkit: https://android-git.corp.google.com/g/#change,117817
   browser: https://android-git.corp.google.com/g/#change,117835

Change-Id: I65c3f038a48b6386fa93cb25a9ef70dbfb982c18