PrerenderingLoader initial integration with PrerenderManager/PrerenderHandle and make it unit-testa…

components/offline_pages/background/offliner.h

 // 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.
 
 #ifndef COMPONENTS_OFFLINE_PAGES_BACKGROUND_OFFLINER_H_
 #define COMPONENTS_OFFLINE_PAGES_BACKGROUND_OFFLINER_H_
 
 #include "base/callback.h"
 
 namespace offline_pages {
 
 class SavePageRequest;
 
 // Interface of a class responsible for constructing an offline page given
 // a request with a URL.
 class Offliner {
  public:
-  // Completion status of processing an offline page request.
-  enum CompletionStatus {
-    SAVED = 0,
-    CANCELED = 1,
-    FAILED_CONSIDER_RETRY = 2,
-    FAILED_DO_NOT_RETRY = 3,
-    UNKNOWN = 4,
+  // Status of processing an offline page request.
+  enum class RequestStatus {
+    UNKNOWN,   // No status determined/reported yet.
+    LOADED,    // Page loaded but not (yet) saved.
+    SAVED,     // Offline page snapshot saved.
+    CANCELED,  // Request was canceled.
+    FAILED,    // Request failed.
+    // TODO(dougarnett): Define a retry-able failure status.
   };
 
   // Reports the completion status of a request.
   // TODO(dougarnett): consider passing back a request id instead of request.
-  typedef base::Callback<void(const SavePageRequest&, CompletionStatus)>
+  typedef base::Callback<void(const SavePageRequest&, RequestStatus)>
       CompletionCallback;
 
   Offliner() {}
   virtual ~Offliner() {}
 
   // Processes |request| to load and save an offline page.
   // Returns whether the request was accepted or not.
   virtual bool LoadAndSave(
       const SavePageRequest& request,
       const CompletionCallback& callback) = 0;
 
   // Clears the currently processing request, if any.
   virtual void Cancel() = 0;
 
   // TODO(dougarnett): add policy support methods.
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_OFFLINER_H_