Don't allow extensions to take screenshots of interstitial pages. Branched from
https://codereview.chromium.org/14885004/ which is trying to test it.

BUG=229504

Review URL: https://chromiumcodereview.appspot.com/14954004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198297 0039d316-1c4b-4281-b951-d872f2087c98
void TabsExecuteScriptFunction::OnExecuteCodeFinished(const std::string& error,
                                                      int32 on_page_id,
                                                      const GURL& on_url,
                                                      const ListValue& result) {
  if (error.empty())
    SetResult(result.DeepCopy());
  ExecuteCodeInTabFunction::OnExecuteCodeFinished(error, on_page_id, on_url,
                                                  result);
}

void TabsExecuteScriptFunction::OnExecuteCodeFinished(const std::string& error,
                                                      int32 on_page_id,
                                                      const GURL& on_url,
                                                      const ListValue& result) {
  if (error.empty())
    SetResult(result.DeepCopy());
  ExecuteCodeInTabFunction::OnExecuteCodeFinished(error, on_page_id, on_url,
                                                  result);
}
