[Most Visited] Check for Sync state when using SuggestionsService.

components/suggestions/suggestions_utils.h

+// Copyright 2014 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.
+
+#ifndef COMPONENTS_SUGGESTIONS_SUGGESTIONS_UTILS_H_
+#define COMPONENTS_SUGGESTIONS_SUGGESTIONS_UTILS_H_
+
+namespace suggestions {
+
+// Establishes the different sync states that users of  SuggestionsService can

[manzagop (departed), 2014/08/20 15:43:51]

nit: double space "of  Sugg...".

[Mathieu, 2014/08/20 18:41:29]

Done.

+// specify. There are three different concepts in the sync service: initialized,
+// sync enabled and history sync enabled.
+enum SyncState {

[manzagop (departed), 2014/08/20 15:43:51]

Nit: how about FetchType: CACHE, SERVER, CLEAR.

Basically, something that centers on the SuggestionsService instead of on Sync.

[Mathieu, 2014/08/20 18:41:30]

Ack. Discussed offline. I don't want users of SuggestionsService to focus on
behavior, but rather on Sync State because it enforces the API and reduces the
possibility of someone just passing the literal SERVER enum as argument.

+  // Sync service is not yet initialized, yet not disabled. History sync state
+  // is unknown (since not initialized).

[manzagop (departed), 2014/08/20 15:43:51]

Maybe document the fetch type, instead of what motivates it? Eg Don't issue a
server request, instead serve suggestions from cache if any.

[Mathieu, 2014/08/20 18:41:29]

Done.

+  NOT_INITIALIZED_ENABLED,
+
+  // Sync service is initialized, sync is enabled and history sync is enabled.
+  INITIALIZED_ENABLED_HISTORY,

[manzagop (departed), 2014/08/20 15:43:51]

Update suggestions from the server. Serve from cache on timeout.

[Mathieu, 2014/08/20 18:41:29]

Done.

+
+  // Sync service is disabled (initialized or not) OR initialized and enabled
+  // with no history sync.
+  DISABLED,

[manzagop (departed), 2014/08/20 15:43:51]

Do not issue a server request. Clear the cache.

[Mathieu, 2014/08/20 18:41:29]

Done.

+};
+
+SyncState GetSyncState(bool sync_initialized,

[manzagop (departed), 2014/08/20 15:43:51]

Perhaps this is where you can document what conditions lead to which FetchType.

[Mathieu, 2014/08/20 18:41:29]

Acknowledged.

+                       bool sync_enabled,
+                       bool history_sync_enabled);
+
+}  // namespace suggestions
+
+#endif  // COMPONENTS_SUGGESTIONS_SUGGESTIONS_UTILS_H_