RemoteSuggestionsFetcher: Use common AccessTokenFetcher helper class

components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc

Index: components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc
diff --git a/components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc b/components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc
index 714c8217a29206d3d6582ac400fe0af6afe21f21..aae9750c86454a576830cab635ac950b3356b3b2 100644
--- a/components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc
+++ b/components/ntp_snippets/remote/remote_suggestions_fetcher_unittest.cc
@@ -399,9 +399,6 @@ class RemoteSuggestionsSignedOutFetcherTest
             GURL(kTestChromeContentSuggestionsSignedOutUrl)) {}
 };
 
-// TODO(jkrcal): Add unit-tests for the "authentication in progress" case as it
-// requires more changes (instead FakeSigninManagerBase use FakeSigninManager
-// which does not exist on ChromeOS). crbug.com/688310
 class RemoteSuggestionsSignedInFetcherTest
     : public RemoteSuggestionsFetcherTestBase {
  public: