Phase III Step 1: Make ImageResourceContent manage its own ResourceStatus

third_party/WebKit/Source/core/loader/resource/ImageResourceContent.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 ImageResourceContent_h
 #define ImageResourceContent_h
 
 #include <memory>
 #include "core/CoreExport.h"
 #include "platform/geometry/IntRect.h"
@@ skipping 75 matching lines @@
 
   void AddObserver(ImageResourceObserver*);
   void RemoveObserver(ImageResourceObserver*);
 
   bool IsSizeAvailable() const {
     return size_available_ == Image::kSizeAvailable;
   }
 
   DECLARE_TRACE();
 
+  // Content status and deriving predicates.
+  // https://docs.google.com/document/d/1O-fB83mrE0B_V8gzXNqHgmRLCvstTB4MMi3RnVLr8bE/edit#heading=h.6cyqmir0f30h
+  // Normal transitions:
+  //   kNotStarted -> kPending -> kCached|kLoadError|kDecodeError.
+  // Additional transitions in multipart images:
+  //   kCached -> kLoadError|kDecodeError.
+  // Transitions due to revalidation:
+  //   kCached -> kPending.
+  // Transitions due to reload:
+  //   kCached|kLoadError|kDecodeError -> kPending.
+  //
+  // ImageResourceContent::GetContentStatus() can be different from
+  // ImageResource::GetStatus(). Use ImageResourceContent::GetContentStatus().
+  ResourceStatus GetContentStatus() const;
+  bool IsLoaded() const;
+  bool IsLoading() const;
+  bool ErrorOccurred() const;
+  bool LoadFailedOrCanceled() const;
+
   // Redirecting methods to Resource.
   const KURL& Url() const;
   bool IsAccessAllowed(SecurityOrigin*);
   const ResourceResponse& GetResponse() const;
-  bool IsLoaded() const;
-  bool IsLoading() const;
-  bool ErrorOccurred() const;
-  bool LoadFailedOrCanceled() const;
-  ResourceStatus GetStatus() const;
   const ResourceError& GetResourceError() const;
 
   // For FrameSerializer.
   bool HasCacheControlNoStoreHeader() const;
 
   void EmulateLoadStartedForInspector(ResourceFetcher*,
                                       const KURL&,
                                       const AtomicString& initiator_name);
 
   void SetNotRefetchableDataFromDiskCache() {
@@ skipping 20 matching lines @@
     kClearImageAndNotifyObservers,
   };
   enum class UpdateImageResult {
     kNoDecodeError,
 
     // Decode error occurred. Observers are not notified.
     // Only occurs when UpdateImage or ClearAndUpdateImage is specified.
     kShouldDecodeError,
   };
   WARN_UNUSED_RESULT UpdateImageResult UpdateImage(PassRefPtr<SharedBuffer>,
+                                                   ResourceStatus,
                                                    UpdateImageOption,
                                                    bool all_data_received);
 
+  void NotifyStartLoad();
   void DestroyDecodedData();
   void DoResetAnimation();
 
   void SetImageResourceInfo(ImageResourceInfo*);
 
   ResourcePriority PriorityFromObservers() const;
   PassRefPtr<const SharedBuffer> ResourceBuffer() const;
   bool ShouldUpdateImageImmediately() const;
   bool HasObservers() const {
     return !observers_.IsEmpty() || !finished_observers_.IsEmpty();
@@ skipping 13 matching lines @@
 
   PassRefPtr<Image> CreateImage();
   void ClearImage();
 
   enum NotifyFinishOption { kShouldNotifyFinish, kDoNotNotifyFinish };
 
   // If not null, changeRect is the changed part of the image.
   void NotifyObservers(NotifyFinishOption,
                        const IntRect* change_rect = nullptr);
   void MarkObserverFinished(ImageResourceObserver*);
+  void UpdateToLoadedContentStatus(ResourceStatus);
 
   class ProhibitAddRemoveObserverInScope : public AutoReset<bool> {
    public:
     ProhibitAddRemoveObserverInScope(const ImageResourceContent* content)
         : AutoReset(&content->is_add_remove_observer_prohibited_, true) {}
   };
 
   Member<ImageResourceInfo> info_;
+  ResourceStatus content_status_ = ResourceStatus::kNotStarted;
 
   RefPtr<blink::Image> image_;
 
   HashCountedSet<ImageResourceObserver*> observers_;
   HashCountedSet<ImageResourceObserver*> finished_observers_;
 
   Image::SizeAvailability size_available_ = Image::kSizeUnavailable;
 
   // Indicates if this resource's encoded image data can be purged and refetched
   // from disk cache to save memory usage. See crbug/664437.
   bool is_refetchable_data_from_disk_cache_;
 
   mutable bool is_add_remove_observer_prohibited_ = false;
 
 #if DCHECK_IS_ON()
   bool is_update_image_being_called_ = false;
 #endif
 };
 
 }  // namespace blink
 
 #endif