Phase II Step 3: Reload LoFi/placeholder images via new ImageResource

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 "core/CoreExport.h"
 #include "core/fetch/ResourceStatus.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/geometry/IntSizeHash.h"
 #include "platform/geometry/LayoutSize.h"
 #include "platform/graphics/Image.h"
 #include "platform/graphics/ImageObserver.h"
 #include "platform/graphics/ImageOrientation.h"
 #include "platform/network/ResourceLoadPriority.h"
 #include "platform/weborigin/KURL.h"
 #include "wtf/HashCountedSet.h"
 #include "wtf/HashMap.h"
 #include <memory>
 
 namespace blink {
 
 class FetchRequest;
+class ImageResource;
 class ImageResourceInfo;
 class ImageResourceObserver;
 class ResourceError;
 class ResourceFetcher;
 class ResourceResponse;
 class SecurityOrigin;
 
 // ImageResourceContent is a container that holds fetch result of
 // an ImageResource in a decoded form.
 // Classes that use the fetched images
@@ skipping 82 matching lines @@
     UpdateImage,
 
     // Clears the image and then updates the image.
     ClearAndUpdateImage,
 
     // Clears the image and notifies observers only (without updating).
     ClearImageOnly,
   };
   void updateImage(PassRefPtr<SharedBuffer>,
                    UpdateImageOption,
-                   bool allDataReceived);
+                   bool allDataReceived,
+                   ResourceFetcher* fetcherForReload);
   ResourcePriority priorityFromObservers() const;
   void destroyDecodedData();
   void doResetAnimation();
   PassRefPtr<const SharedBuffer> resourceBuffer() const;
   bool shouldUpdateImageImmediately() const;
   bool hasObservers() const {
     return !m_observers.isEmpty() || !m_finishedObservers.isEmpty();
   }
   bool isRefetchableDataFromDiskCache() const {
     return m_isRefetchableDataFromDiskCache;
   }
 
+  // Only for tests.
+  const ImageResource* resourceForTest() const;

[Nate Chapin, 2016/12/28 00:14:58]

This is a pretty bad layering violation, right? But at least it's test-only? :/

[hiroshige, 2017/01/25 02:01:49]

Yes, bad violation.
This is currently needed for tests to retrieve the new ImageResource used for
reloading, because reloading can be initiated inside
ResourceLoader::didReveiveData(), and thus tests don't have direct access to
reloading interface.

I removed this by retrieving the new ImageResource for reloading from
ResourceFetcher::cachedResource() in the unit tests.
This is not super clean, but this doesn't affect non-test code.

+
  private:
   explicit ImageResourceContent(PassRefPtr<blink::Image> = nullptr);
 
   // ImageObserver
   void decodedSizeChangedTo(const blink::Image*, size_t newSize) override;
   bool shouldPauseAnimation(const blink::Image*) override;
   void animationAdvanced(const blink::Image*) override;
   void changedInRect(const blink::Image*, const IntRect&) override;
 
   PassRefPtr<Image> createImage();
@@ skipping 15 matching lines @@
   Image::SizeAvailability m_sizeAvailable = Image::SizeUnavailable;
 
   // Indicates if this resource's encoded image data can be purged and refetched
   // from disk cache to save memory usage. See crbug/664437.
   bool m_isRefetchableDataFromDiskCache;
 };
 
 }  // namespace blink
 
 #endif