FetchMore functionality backend

components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/ntp_snippets/bookmarks/bookmark_suggestions_provider.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 134 matching lines @@
   MarkBookmarksDismissed(bookmark_model_, url);
 }
 
 void BookmarkSuggestionsProvider::FetchSuggestionImage(
     const ContentSuggestion::ID& suggestion_id,
     const ImageFetchedCallback& callback) {
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(callback, gfx::Image()));
 }
 
+void BookmarkSuggestionsProvider::FetchMore(const Category& category,
+                                            FetchedMoreCallback callback) {
+  // Ignored.

[Marc Treib, 2016/10/20 16:51:39]

Hm. In principle, the bookmarks provider (like most/all others) could implement
"more" functionality. Right now there's no way to access it, because the "more"
button instead opens the bookmark manager. But have you discussed this with
Patrick?
If we don't expect to ever get here, then put a NOTREACHED() there.

[Marc Treib, 2016/10/28 14:49:49]

I discussed this with dgn and bauerb: We'll unify "get suggestions" (currently
implemented via the observer) and "fetch more". They'll fill you in on the
details :)

+}
+
 void BookmarkSuggestionsProvider::ClearHistory(
     base::Time begin,
     base::Time end,
     const base::Callback<bool(const GURL& url)>& filter) {
   // TODO(vitaliii): Do not remove all dates, but only the ones matched by the
   // time range and the filter.
   RemoveAllLastVisitDates(bookmark_model_);
   ClearDismissedSuggestionsForDebugging(provided_category_);
   FetchBookmarks();
   // Temporarily enter an "explicitly disabled" state, so that any open UIs
@@ skipping 138 matching lines @@
 
 void BookmarkSuggestionsProvider::NotifyStatusChanged(
     CategoryStatus new_status) {
   if (category_status_ == new_status)
     return;
   category_status_ = new_status;
   observer()->OnCategoryStatusChanged(this, provided_category_, new_status);
 }
 
 }  // namespace ntp_snippets