[Remote suggestions] Move all decisions to fetch to the scheduler

components/ntp_snippets/remote/remote_suggestions_provider.h

 // Copyright 2015 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_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_
 #define COMPONENTS_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "components/ntp_snippets/content_suggestions_provider.h"
 
 namespace ntp_snippets {
 
 class RemoteSuggestionsFetcher;
 
 // Retrieves fresh content data (articles) from the server, stores them and
 // provides them as content suggestions.
 class RemoteSuggestionsProvider : public ContentSuggestionsProvider {
  public:
-  // TODO(jkrcal): Would be nice to get rid of this another level of statuses.
-  // Maybe possible while refactoring the RemoteSuggestionsStatusService? (and
-  // letting it notify both the SchedulingRemoteSuggestionsProvider and
-  // RemoteSuggestionsProviderImpl or just the scheduling one).
-  enum class ProviderStatus { ACTIVE, INACTIVE };
-  using ProviderStatusCallback =
-      base::RepeatingCallback<void(ProviderStatus status)>;
-
   // Callback to notify with the result of a fetch.
   // TODO(jkrcal): Change to OnceCallback? A OnceCallback does only have a
   // move-constructor which seems problematic for google mock.
   using FetchStatusCallback = base::Callback<void(Status status_code)>;
 
   ~RemoteSuggestionsProvider() override;
 
-  // Set a callback to be notified whenever the status of the provider changes.
-  // The initial change is also notified (switching from an initial undecided
-  // status). If the callback is set after the first change, it is called back
-  // immediately.
-  // TODO(treib): Get rid of unique_ptrs to callbacks.
-  virtual void SetProviderStatusCallback(
-      std::unique_ptr<ProviderStatusCallback> callback) = 0;
-
   // Fetches suggestions from the server for all remote categories and replaces
   // old suggestions by the new ones. The request to the server is performed as
   // an background request. Background requests are used for actions not
   // triggered by the user and have lower priority on the server. After the
   // fetch finished, the provided |callback| will be triggered with the status
   // of the fetch (unless nullptr).
   virtual void RefetchInTheBackground(
       std::unique_ptr<FetchStatusCallback> callback) = 0;
 
   virtual const RemoteSuggestionsFetcher* suggestions_fetcher_for_debugging()
       const = 0;
 
  protected:
   RemoteSuggestionsProvider(Observer* observer);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_REMOTE_REMOTE_SUGGESTIONS_PROVIDER_H_