[ImageResource 4] Split ImageResource into Resource and Image parts

third_party/WebKit/Source/core/fetch/ImageResourceContent.cpp

Index: third_party/WebKit/Source/core/fetch/ImageResourceContent.cpp
diff --git a/third_party/WebKit/Source/core/fetch/ImageResource.cpp b/third_party/WebKit/Source/core/fetch/ImageResourceContent.cpp
similarity index 30%
copy from third_party/WebKit/Source/core/fetch/ImageResource.cpp
copy to third_party/WebKit/Source/core/fetch/ImageResourceContent.cpp
index 82152c1d79564dfee668d594b241e71a9022a0f0..4387c12fbcb50fcc65ec816f20f1c32d81b6541c 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResourceContent.cpp
@@ -1,34 +1,12 @@
-/*
-    Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
-    Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
-    Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
-    Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
-    Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
-
-    This library is free software; you can redistribute it and/or
-    modify it under the terms of the GNU Library General Public
-    License as published by the Free Software Foundation; either
-    version 2 of the License, or (at your option) any later version.
-
-    This library is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-    Library General Public License for more details.
-
-    You should have received a copy of the GNU Library General Public License
-    along with this library; see the file COPYING.LIB.  If not, write to
-    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
-    Boston, MA 02110-1301, USA.
-*/
+// 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.
 
-#include "core/fetch/ImageResource.h"
+#include "core/fetch/ImageResourceContent.h"
 
+#include "core/fetch/ImageResource.h"
+#include "core/fetch/ImageResourceInfo.h"
 #include "core/fetch/ImageResourceObserver.h"
-#include "core/fetch/MemoryCache.h"
-#include "core/fetch/ResourceClient.h"
-#include "core/fetch/ResourceFetcher.h"
-#include "core/fetch/ResourceLoader.h"
-#include "core/fetch/ResourceLoadingLog.h"
 #include "core/svg/graphics/SVGImage.h"
 #include "platform/Histogram.h"
 #include "platform/RuntimeEnabledFeatures.h"
@@ -37,10 +15,6 @@
 #include "platform/graphics/BitmapImage.h"
 #include "platform/graphics/PlaceholderImage.h"
 #include "platform/tracing/TraceEvent.h"
-#include "public/platform/Platform.h"
-#include "public/platform/WebCachePolicy.h"
-#include "wtf/CurrentTime.h"
-#include "wtf/HashCountedSet.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/Vector.h"
 #include <memory>
@@ -48,116 +22,80 @@
 
 namespace blink {
 namespace {
-// The amount of time to wait before informing the clients that the image has
-// been updated (in seconds). This effectively throttles invalidations that
-// result from new data arriving for this image.
-constexpr double kFlushDelaySeconds = 1.;
-}  // namespace
-
-class ImageResource::ImageResourceFactory : public ResourceFactory {
-  STACK_ALLOCATED();
+class NullImageResourceInfo final
+    : public GarbageCollectedFinalized<NullImageResourceInfo>,
+      public ImageResourceInfo {
+  USING_GARBAGE_COLLECTED_MIXIN(NullImageResourceInfo);
 
  public:
-  ImageResourceFactory(const FetchRequest& fetchRequest)
-      : ResourceFactory(Resource::Image), m_fetchRequest(&fetchRequest) {}
-
-  Resource* create(const ResourceRequest& request,
-                   const ResourceLoaderOptions& options,
-                   const String&) const override {
-    return new ImageResource(request, options,
-                             m_fetchRequest->placeholderImageRequestType() ==
-                                 FetchRequest::AllowPlaceholder);
-  }
+  NullImageResourceInfo() {}
 
- private:
-  // Weak, unowned pointer. Must outlive |this|.
-  const FetchRequest* m_fetchRequest;
-};
+  DEFINE_INLINE_VIRTUAL_TRACE() { ImageResourceInfo::trace(visitor); }
 
-ImageResource* ImageResource::fetch(FetchRequest& request,
-                                    ResourceFetcher* fetcher) {
-  if (request.resourceRequest().requestContext() ==
-      WebURLRequest::RequestContextUnspecified) {
-    request.mutableResourceRequest().setRequestContext(
-        WebURLRequest::RequestContextImage);
+ private:
+  const KURL& url() const override { return m_url; }
+  bool isSchedulingReload() const override { return false; }
+  bool hasDevicePixelRatioHeaderValue() const override { return false; }
+  float devicePixelRatioHeaderValue() const override { return 1.0; }
+  const ResourceResponse& response() const override { return m_response; }
+  ResourceStatus getStatus() const override { return ResourceStatus::Cached; }
+  bool isPlaceholder() const override { return false; }
+  bool isCacheValidator() const override { return false; }
+  bool schedulingReloadOrShouldReloadBrokenPlaceholder() const override {
+    return false;
   }
-  if (fetcher->context().pageDismissalEventBeingDispatched()) {
-    KURL requestURL = request.resourceRequest().url();
-    if (requestURL.isValid()) {
-      ResourceRequestBlockedReason blockReason = fetcher->context().canRequest(
-          Resource::Image, request.resourceRequest(), requestURL,
-          request.options(), request.forPreload(),
-          request.getOriginRestriction());
-      if (blockReason == ResourceRequestBlockedReason::None)
-        fetcher->context().sendImagePing(requestURL);
-    }
-    return nullptr;
+  bool isAccessAllowed(
+      SecurityOrigin*,
+      DoesCurrentFrameHaveSingleSecurityOrigin) const override {
+    return true;
   }
+  bool hasCacheControlNoStoreHeader() const override { return false; }
+  const ResourceError& resourceError() const override { return m_error; }
+
+  void decodeError(bool allDataReceived) override {}
+  void setDecodedSize(size_t) override {}
+  void willAddClientOrObserver() override {}
+  void didRemoveClientOrObserver() override {}
+  void emulateLoadStartedForInspector(
+      ResourceFetcher*,
+      const KURL&,
+      const AtomicString& initiatorName) override {}
+
+  const KURL m_url;
+  const ResourceResponse m_response;
+  const ResourceError m_error;
+};
 
-  ImageResource* resource = toImageResource(
-      fetcher->requestResource(request, ImageResourceFactory(request)));
-  if (resource &&
-      request.placeholderImageRequestType() != FetchRequest::AllowPlaceholder &&
-      resource->m_isPlaceholder) {
-    // If the image is a placeholder, but this fetch doesn't allow a
-    // placeholder, then load the original image. Note that the cache is not
-    // bypassed here - it should be fine to use a cached copy if possible.
-    resource->reloadIfLoFiOrPlaceholder(fetcher,
-                                        ReloadCachePolicy::UseExistingPolicy);
-  }
-  return resource;
-}
-
-ImageResource::ImageResource(const ResourceRequest& resourceRequest,
-                             const ResourceLoaderOptions& options,
-                             bool isPlaceholder)
-    : Resource(resourceRequest, Image, options),
-      m_devicePixelRatioHeaderValue(1.0),
-      m_image(nullptr),
-      m_hasDevicePixelRatioHeaderValue(false),
-      m_isSchedulingReload(false),
-      m_isPlaceholder(isPlaceholder),
-      m_flushTimer(this, &ImageResource::flushImageIfNeeded),
-      m_isRefetchableDataFromDiskCache(true) {
-  RESOURCE_LOADING_DVLOG(1) << "new ImageResource(ResourceRequest) " << this;
-}
-
-ImageResource::ImageResource(blink::Image* image,
-                             const ResourceLoaderOptions& options)
-    : Resource(ResourceRequest(""), Image, options),
-      m_devicePixelRatioHeaderValue(1.0),
-      m_image(image),
-      m_hasDevicePixelRatioHeaderValue(false),
-      m_isSchedulingReload(false),
-      m_isPlaceholder(false),
-      m_flushTimer(this, &ImageResource::flushImageIfNeeded),
-      m_isRefetchableDataFromDiskCache(true) {
-  RESOURCE_LOADING_DVLOG(1) << "new ImageResource(Image) " << this;
-  setStatus(Cached);
-}
-
-ImageResource::~ImageResource() {
-  RESOURCE_LOADING_DVLOG(1) << "~ImageResource " << this;
-  clearImage();
+}  // namespace
+
+ImageResourceContent::ImageResourceContent(PassRefPtr<blink::Image> image)
+    : m_image(image), m_isRefetchableDataFromDiskCache(true) {
+  DEFINE_STATIC_LOCAL(NullImageResourceInfo, nullInfo,
+                      (new NullImageResourceInfo()));
+  m_info = &nullInfo;
 }
 
-DEFINE_TRACE(ImageResource) {
-  visitor->trace(m_multipartParser);
-  Resource::trace(visitor);
-  ImageObserver::trace(visitor);
-  MultipartImageResourceParser::Client::trace(visitor);
+ImageResourceContent* ImageResourceContent::fetch(FetchRequest& request,
+                                                  ResourceFetcher* fetcher) {
+  // TODO(hiroshige): Remove direct references to ImageResource by making
+  // the dependencies around ImageResource and ImageResourceContent cleaner.
+  ImageResource* resource = ImageResource::fetch(request, fetcher);
+  if (!resource)
+    return nullptr;
+  return resource->getContent();
 }
 
-void ImageResource::checkNotify() {
-  // Don't notify clients of completion if this ImageResource is
-  // about to be reloaded.
-  if (m_isSchedulingReload || shouldReloadBrokenPlaceholder())
-    return;
+void ImageResourceContent::setImageResourceInfo(ImageResourceInfo* info) {
+  m_info = info;
+}
 
-  Resource::checkNotify();
+DEFINE_TRACE(ImageResourceContent) {
+  visitor->trace(m_info);
+  ImageObserver::trace(visitor);
 }
 
-void ImageResource::markObserverFinished(ImageResourceObserver* observer) {
+void ImageResourceContent::markObserverFinished(
+    ImageResourceObserver* observer) {
   auto it = m_observers.find(observer);
   if (it == m_observers.end())
     return;
@@ -165,47 +103,26 @@ void ImageResource::markObserverFinished(ImageResourceObserver* observer) {
   m_finishedObservers.add(observer);
 }
 
-void ImageResource::didAddClient(ResourceClient* client) {
-  DCHECK((m_multipartParser && isLoading()) || !data() || m_image);
-
-  // Don't notify observers and clients of completion if this ImageResource is
-  // about to be reloaded.
-  if (m_isSchedulingReload || shouldReloadBrokenPlaceholder())
-    return;
-
-  Resource::didAddClient(client);
-}
-
-void ImageResource::addObserver(ImageResourceObserver* observer) {
-  willAddClientOrObserver(MarkAsReferenced);
+void ImageResourceContent::addObserver(ImageResourceObserver* observer) {
+  m_info->willAddClientOrObserver();
 
   m_observers.add(observer);
 
-  if (isCacheValidator())
+  if (m_info->isCacheValidator())
     return;
 
-  // When the response is not multipart, if |data()| exists, |m_image| must be
-  // created. This is assured that |updateImage()| is called when |appendData()|
-  // is called.
-  //
-  // On the other hand, when the response is multipart, |updateImage()| is not
-  // called in |appendData()|, which means |m_image| might not be created even
-  // when |data()| exists. This is intentional since creating a |m_image| on
-  // receiving data might destroy an existing image in a previous part.
-  DCHECK((m_multipartParser && isLoading()) || !data() || m_image);
-
   if (m_image && !m_image->isNull()) {
     observer->imageChanged(this);
   }
 
-  if (isLoaded() && m_observers.contains(observer) && !m_isSchedulingReload &&
-      !shouldReloadBrokenPlaceholder()) {
+  if (isLoaded() && m_observers.contains(observer) &&
+      !m_info->schedulingReloadOrShouldReloadBrokenPlaceholder()) {
     markObserverFinished(observer);
     observer->imageNotifyFinished(this);
   }
 }
 
-void ImageResource::removeObserver(ImageResourceObserver* observer) {
+void ImageResourceContent::removeObserver(ImageResourceObserver* observer) {
   DCHECK(observer);
 
   auto it = m_observers.find(observer);
@@ -216,7 +133,7 @@ void ImageResource::removeObserver(ImageResourceObserver* observer) {
     DCHECK(it != m_finishedObservers.end());
     m_finishedObservers.remove(it);
   }
-  didRemoveClientOrObserver();
+  m_info->didRemoveClientOrObserver();
 }
 
 static void priorityFromObserver(const ImageResourceObserver* observer,
@@ -228,7 +145,7 @@ static void priorityFromObserver(const ImageResourceObserver* observer,
   priority.intraPriorityValue += nextPriority.intraPriorityValue;
 }
 
-ResourcePriority ImageResource::priorityFromObservers() {
+ResourcePriority ImageResourceContent::priorityFromObservers() const {
   ResourcePriority priority;
 
   for (const auto& it : m_finishedObservers)
@@ -239,100 +156,34 @@ ResourcePriority ImageResource::priorityFromObservers() {
   return priority;
 }
 
-void ImageResource::destroyDecodedDataForFailedRevalidation() {
-  clearImage();
-  setDecodedSize(0);
-}
-
-void ImageResource::destroyDecodedDataIfPossible() {
+void ImageResourceContent::destroyDecodedData() {
   if (!m_image)
     return;
   CHECK(!errorOccurred());
   m_image->destroyDecodedData();
-  if (!isPreloaded() && m_isRefetchableDataFromDiskCache) {
-    UMA_HISTOGRAM_MEMORY_KB("Memory.Renderer.EstimatedDroppableEncodedSize",
-                            encodedSize() / 1024);
-  }
 }
 
-void ImageResource::doResetAnimation() {
+void ImageResourceContent::doResetAnimation() {
   if (m_image)
     m_image->resetAnimation();
 }
 
-void ImageResource::allClientsAndObserversRemoved() {
-  if (m_image) {
-    CHECK(!errorOccurred());
-    // If possible, delay the resetting until back at the event loop. Doing so
-    // after a conservative GC prevents resetAnimation() from upsetting ongoing
-    // animation updates (crbug.com/613709)
-    if (!ThreadHeap::willObjectBeLazilySwept(this)) {
-      Platform::current()->currentThread()->getWebTaskRunner()->postTask(
-          BLINK_FROM_HERE, WTF::bind(&ImageResource::doResetAnimation,
-                                     wrapWeakPersistent(this)));
-    } else {
-      m_image->resetAnimation();
-    }
-  }
-  if (m_multipartParser)
-    m_multipartParser->cancel();
-  Resource::allClientsAndObserversRemoved();
-}
-
-PassRefPtr<const SharedBuffer> ImageResource::resourceBuffer() const {
-  if (data())
-    return data();
+PassRefPtr<const SharedBuffer> ImageResourceContent::resourceBuffer() const {
   if (m_image)
     return m_image->data();
   return nullptr;
 }
 
-void ImageResource::appendData(const char* data, size_t length) {
-  v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(length);
-  if (m_multipartParser) {
-    m_multipartParser->appendData(data, length);
-  } else {
-    Resource::appendData(data, length);
-
-    // If we don't have the size available yet, then update immediately since
-    // we need to know the image size as soon as possible. Likewise for
-    // animated images, update right away since we shouldn't throttle animated
-    // images.
-    if (m_sizeAvailable == Image::SizeUnavailable ||
-        (m_image && m_image->maybeAnimated())) {
-      updateImage(false);
-      return;
-    }
-
-    // For other cases, only update at |kFlushDelaySeconds| intervals. This
-    // throttles how frequently we update |m_image| and how frequently we
-    // inform the clients which causes an invalidation of this image. In other
-    // words, we only invalidate this image every |kFlushDelaySeconds| seconds
-    // while loading.
-    if (!m_flushTimer.isActive()) {
-      double now = WTF::monotonicallyIncreasingTime();
-      if (!m_lastFlushTime)
-        m_lastFlushTime = now;
-
-      DCHECK_LE(m_lastFlushTime, now);
-      double flushDelay = m_lastFlushTime - now + kFlushDelaySeconds;
-      if (flushDelay < 0.)
-        flushDelay = 0.;
-      m_flushTimer.startOneShot(flushDelay, BLINK_FROM_HERE);
-    }
-  }
-}
-
-void ImageResource::flushImageIfNeeded(TimerBase*) {
-  // We might have already loaded the image fully, in which case we don't need
-  // to call |updateImage()|.
-  if (isLoading()) {
-    m_lastFlushTime = WTF::monotonicallyIncreasingTime();
-    updateImage(false);
-  }
+bool ImageResourceContent::shouldUpdateImageImmediately() const {
+  // If we don't have the size available yet, then update immediately since
+  // we need to know the image size as soon as possible. Likewise for
+  // animated images, update right away since we shouldn't throttle animated
+  // images.
+  return m_sizeAvailable == Image::SizeUnavailable ||
+         (m_image && m_image->maybeAnimated());
 }
 
-std::pair<blink::Image*, float> ImageResource::brokenImage(
+std::pair<blink::Image*, float> ImageResourceContent::brokenImage(
     float deviceScaleFactor) {
   if (deviceScaleFactor >= 2) {
     DEFINE_STATIC_REF(blink::Image, brokenImageHiRes,
@@ -345,15 +196,11 @@ std::pair<blink::Image*, float> ImageResource::brokenImage(
   return std::make_pair(brokenImageLoRes, 1);
 }
 
-bool ImageResource::willPaintBrokenImage() const {
-  return errorOccurred();
-}
-
-blink::Image* ImageResource::getImage() {
+blink::Image* ImageResourceContent::getImage() {
   if (errorOccurred()) {
     // Returning the 1x broken image is non-ideal, but we cannot reliably access
     // the appropriate deviceScaleFactor from here. It is critical that callers
-    // use ImageResource::brokenImage() when they need the real,
+    // use ImageResourceContent::brokenImage() when they need the real,
     // deviceScaleFactor-appropriate broken image icon.
     return brokenImage(1).first;
   }
@@ -364,21 +211,21 @@ blink::Image* ImageResource::getImage() {
   return blink::Image::nullImage();
 }
 
-bool ImageResource::usesImageContainerSize() const {
+bool ImageResourceContent::usesImageContainerSize() const {
   if (m_image)
     return m_image->usesContainerSize();
 
   return false;
 }
 
-bool ImageResource::imageHasRelativeSize() const {
+bool ImageResourceContent::imageHasRelativeSize() const {
   if (m_image)
     return m_image->hasRelativeSize();
 
   return false;
 }
 
-LayoutSize ImageResource::imageSize(
+LayoutSize ImageResourceContent::imageSize(
     RespectImageOrientationEnum shouldRespectImageOrientation,
     float multiplier,
     SizeType sizeType) {
@@ -395,9 +242,9 @@ LayoutSize ImageResource::imageSize(
     size = LayoutSize(m_image->size());
   }
 
-  if (sizeType == IntrinsicCorrectedToDPR && m_hasDevicePixelRatioHeaderValue &&
-      m_devicePixelRatioHeaderValue > 0)
-    multiplier = 1 / m_devicePixelRatioHeaderValue;
+  if (sizeType == IntrinsicCorrectedToDPR && hasDevicePixelRatioHeaderValue() &&
+      devicePixelRatioHeaderValue() > 0)
+    multiplier = 1 / devicePixelRatioHeaderValue();
 
   if (multiplier == 1 || m_image->hasRelativeSize())
     return size;
@@ -411,8 +258,9 @@ LayoutSize ImageResource::imageSize(
   return size;
 }
 
-void ImageResource::notifyObservers(NotifyFinishOption notifyingFinishOption,
-                                    const IntRect* changeRect) {
+void ImageResourceContent::notifyObservers(
+    NotifyFinishOption notifyingFinishOption,
+    const IntRect* changeRect) {
   for (auto* observer : m_finishedObservers.asVector()) {
     if (m_finishedObservers.contains(observer))
       observer->imageChanged(this, changeRect);
@@ -421,8 +269,8 @@ void ImageResource::notifyObservers(NotifyFinishOption notifyingFinishOption,
     if (m_observers.contains(observer)) {
       observer->imageChanged(this, changeRect);
       if (notifyingFinishOption == ShouldNotifyFinish &&
-          m_observers.contains(observer) && !m_isSchedulingReload &&
-          !shouldReloadBrokenPlaceholder()) {
+          m_observers.contains(observer) &&
+          !m_info->schedulingReloadOrShouldReloadBrokenPlaceholder()) {
         markObserverFinished(observer);
         observer->imageNotifyFinished(this);
       }
@@ -430,25 +278,13 @@ void ImageResource::notifyObservers(NotifyFinishOption notifyingFinishOption,
   }
 }
 
-void ImageResource::clear() {
-  clearImage();
-  clearData();
-  setEncodedSize(0);
-}
-
-inline void ImageResource::createImage() {
-  // Create the image if it doesn't yet exist.
-  if (m_image)
-    return;
-
-  if (response().mimeType() == "image/svg+xml") {
-    m_image = SVGImage::create(this);
-  } else {
-    m_image = BitmapImage::create(this);
-  }
+PassRefPtr<Image> ImageResourceContent::createImage() {
+  if (m_info->response().mimeType() == "image/svg+xml")
+    return SVGImage::create(this);
+  return BitmapImage::create(this);
 }
 
-inline void ImageResource::clearImage() {
+void ImageResourceContent::clearImage() {
   if (!m_image)
     return;
   int64_t length = m_image->data() ? m_image->data()->size() : 0;
@@ -461,18 +297,29 @@ inline void ImageResource::clearImage() {
   m_sizeAvailable = Image::SizeUnavailable;
 }
 
-void ImageResource::updateImage(bool allDataReceived) {
-  TRACE_EVENT0("blink", "ImageResource::updateImage");
+void ImageResourceContent::clearImageAndNotifyObservers(
+    NotifyFinishOption notifyingFinishOption) {
+  clearImage();
+  notifyObservers(notifyingFinishOption);
+}
+
+void ImageResourceContent::updateImage(PassRefPtr<SharedBuffer> data,
+                                       ClearImageOption clearImageOption,
+                                       bool allDataReceived) {
+  TRACE_EVENT0("blink", "ImageResourceContent::updateImage");
 
-  if (data())
-    createImage();
+  if (clearImageOption == ImageResourceContent::ClearExistingImage) {
+    clearImage();
+  }
 
   // Have the image update its data from its internal buffer. It will not do
   // anything now, but will delay decoding until queried for info (like size or
   // specific image frames).
-  if (data()) {
+  if (data) {
+    if (!m_image)
+      m_image = createImage();
     DCHECK(m_image);
-    m_sizeAvailable = m_image->setData(data(), allDataReceived);
+    m_sizeAvailable = m_image->setData(std::move(data), allDataReceived);
   }
 
   // Go ahead and tell our observers to try to draw if we have either received
@@ -481,12 +328,14 @@ void ImageResource::updateImage(bool allDataReceived) {
   if (m_sizeAvailable == Image::SizeUnavailable && !allDataReceived)
     return;
 
-  if (m_isPlaceholder && allDataReceived && m_image && !m_image->isNull()) {
+  if (m_info->isPlaceholder() && allDataReceived && m_image &&
+      !m_image->isNull()) {
     if (m_sizeAvailable == Image::SizeAvailable) {
       // TODO(sclittle): Show the original image if the response consists of the
       // entire image, such as if the entire image response body is smaller than
       // the requested range.
       IntSize dimensions = m_image->size();
+
       clearImage();
       m_image = PlaceholderImage::create(this, dimensions);
     } else {
@@ -497,14 +346,8 @@ void ImageResource::updateImage(bool allDataReceived) {
   }
 
   if (!m_image || m_image->isNull()) {
-    size_t size = encodedSize();
-    clear();
-    if (!errorOccurred())
-      setStatus(DecodeError);
-    if (!allDataReceived && loader()) {
-      loader()->didFinishLoading(monotonicallyIncreasingTime(), size, size);
-    }
-    memoryCache()->remove(this);
+    clearImage();
+    m_info->decodeError(allDataReceived);
   }
 
   // It would be nice to only redraw the decoded band of the image, but with the
@@ -512,70 +355,15 @@ void ImageResource::updateImage(bool allDataReceived) {
   notifyObservers(allDataReceived ? ShouldNotifyFinish : DoNotNotifyFinish);
 }
 
-void ImageResource::updateImageAndClearBuffer() {
-  clearImage();
-  updateImage(true);
-  clearData();
-}
-
-void ImageResource::finish(double loadFinishTime) {
-  if (m_multipartParser) {
-    m_multipartParser->finish();
-    if (data())
-      updateImageAndClearBuffer();
-  } else {
-    updateImage(true);
-    // As encoded image data can be created from m_image  (see
-    // ImageResource::resourceBuffer(), we don't have to keep m_data. Let's
-    // clear this. As for the lifetimes of m_image and m_data, see this
-    // document:
-    // https://docs.google.com/document/d/1v0yTAZ6wkqX2U_M6BNIGUJpM1s0TIw1VsqpxoL7aciY/edit?usp=sharing
-    clearData();
-  }
-  Resource::finish(loadFinishTime);
-}
-
-void ImageResource::error(const ResourceError& error) {
-  if (m_multipartParser)
-    m_multipartParser->cancel();
-  clear();
-  Resource::error(error);
-  notifyObservers(ShouldNotifyFinish);
-}
-
-void ImageResource::responseReceived(
-    const ResourceResponse& response,
-    std::unique_ptr<WebDataConsumerHandle> handle) {
-  DCHECK(!handle);
-  DCHECK(!m_multipartParser);
-  // If there's no boundary, just handle the request normally.
-  if (response.isMultipart() && !response.multipartBoundary().isEmpty()) {
-    m_multipartParser = new MultipartImageResourceParser(
-        response, response.multipartBoundary(), this);
-  }
-  Resource::responseReceived(response, std::move(handle));
-  if (RuntimeEnabledFeatures::clientHintsEnabled()) {
-    m_devicePixelRatioHeaderValue =
-        this->response()
-            .httpHeaderField(HTTPNames::Content_DPR)
-            .toFloat(&m_hasDevicePixelRatioHeaderValue);
-    if (!m_hasDevicePixelRatioHeaderValue ||
-        m_devicePixelRatioHeaderValue <= 0.0) {
-      m_devicePixelRatioHeaderValue = 1.0;
-      m_hasDevicePixelRatioHeaderValue = false;
-    }
-  }
-}
-
-void ImageResource::decodedSizeChangedTo(const blink::Image* image,
-                                         size_t newSize) {
+void ImageResourceContent::decodedSizeChangedTo(const blink::Image* image,
+                                                size_t newSize) {
   if (!image || image != m_image)
     return;
 
-  setDecodedSize(newSize);
+  m_info->setDecodedSize(newSize);
 }
 
-bool ImageResource::shouldPauseAnimation(const blink::Image* image) {
+bool ImageResourceContent::shouldPauseAnimation(const blink::Image* image) {
   if (!image || image != m_image)
     return false;
 
@@ -590,13 +378,13 @@ bool ImageResource::shouldPauseAnimation(const blink::Image* image) {
   return true;
 }
 
-void ImageResource::animationAdvanced(const blink::Image* image) {
+void ImageResourceContent::animationAdvanced(const blink::Image* image) {
   if (!image || image != m_image)
     return;
   notifyObservers(DoNotNotifyFinish);
 }
 
-void ImageResource::updateImageAnimationPolicy() {
+void ImageResourceContent::updateImageAnimationPolicy() {
   if (!m_image)
     return;
 
@@ -616,103 +404,72 @@ void ImageResource::updateImageAnimationPolicy() {
   }
 }
 
-static bool isLoFiImage(const ImageResource& resource) {
-  if (resource.resourceRequest().loFiState() != WebURLRequest::LoFiOn)
-    return false;
-  return !resource.isLoaded() ||
-         resource.response()
-             .httpHeaderField("chrome-proxy-content-transform")
-             .contains("empty-image");
+void ImageResourceContent::changedInRect(const blink::Image* image,
+                                         const IntRect& rect) {
+  if (!image || image != m_image)
+    return;
+  notifyObservers(DoNotNotifyFinish, &rect);
 }
 
-void ImageResource::reloadIfLoFiOrPlaceholder(
-    ResourceFetcher* fetcher,
-    ReloadCachePolicy reloadCachePolicy) {
-  if (!m_isPlaceholder && !isLoFiImage(*this))
-    return;
+bool ImageResourceContent::isAccessAllowed(SecurityOrigin* securityOrigin) {
+  return m_info->isAccessAllowed(
+      securityOrigin, getImage()->currentFrameHasSingleSecurityOrigin()
+                          ? ImageResourceInfo::HasSingleSecurityOrigin
+                          : ImageResourceInfo::HasMultipleSecurityOrigin);
+}
 
-  // Prevent clients and observers from being notified of completion while the
-  // reload is being scheduled, so that e.g. canceling an existing load in
-  // progress doesn't cause clients and observers to be notified of completion
-  // prematurely.
-  DCHECK(!m_isSchedulingReload);
-  m_isSchedulingReload = true;
+void ImageResourceContent::emulateLoadStartedForInspector(
+    ResourceFetcher* fetcher,
+    const KURL& url,
+    const AtomicString& initiatorName) {
+  m_info->emulateLoadStartedForInspector(fetcher, url, initiatorName);
+}
 
-  if (reloadCachePolicy == ReloadCachePolicy::BypassCache)
-    setCachePolicyBypassingCache();
-  setLoFiStateOff();
+// TODO(hiroshige): Consider removing the following methods, or stoping
+// redirecting to ImageResource.
+bool ImageResourceContent::isLoaded() const {
+  return getStatus() > ResourceStatus::Pending;
+}
 
-  if (m_isPlaceholder) {
-    m_isPlaceholder = false;
-    clearRangeRequestHeader();
-  }
+bool ImageResourceContent::isLoading() const {
+  return getStatus() == ResourceStatus::Pending;
+}
 
-  if (isLoading()) {
-    loader()->cancel();
-    // Canceling the loader causes error() to be called, which in turn calls
-    // clear() and notifyObservers(), so there's no need to call these again
-    // here.
-  } else {
-    clear();
-    notifyObservers(DoNotNotifyFinish);
-  }
+bool ImageResourceContent::errorOccurred() const {
+  return getStatus() == ResourceStatus::LoadError ||
+         getStatus() == ResourceStatus::DecodeError;
+}
 
-  setStatus(NotStarted);
+bool ImageResourceContent::loadFailedOrCanceled() const {
+  return getStatus() == ResourceStatus::LoadError;
+}
 
-  DCHECK(m_isSchedulingReload);
-  m_isSchedulingReload = false;
+ResourceStatus ImageResourceContent::getStatus() const {
+  return m_info->getStatus();
+}
 
-  fetcher->startLoad(this);
+const KURL& ImageResourceContent::url() const {
+  return m_info->url();
 }
 
-void ImageResource::changedInRect(const blink::Image* image,
-                                  const IntRect& rect) {
-  if (!image || image != m_image)
-    return;
-  notifyObservers(DoNotNotifyFinish, &rect);
+bool ImageResourceContent::hasCacheControlNoStoreHeader() const {
+  return m_info->hasCacheControlNoStoreHeader();
 }
 
-void ImageResource::onePartInMultipartReceived(
-    const ResourceResponse& response) {
-  DCHECK(m_multipartParser);
+float ImageResourceContent::devicePixelRatioHeaderValue() const {
+  return m_info->devicePixelRatioHeaderValue();
+}
 
-  setResponse(response);
-  if (m_multipartParsingState == MultipartParsingState::WaitingForFirstPart) {
-    // We have nothing to do because we don't have any data.
-    m_multipartParsingState = MultipartParsingState::ParsingFirstPart;
-    return;
-  }
-  updateImageAndClearBuffer();
-
-  if (m_multipartParsingState == MultipartParsingState::ParsingFirstPart) {
-    m_multipartParsingState = MultipartParsingState::FinishedParsingFirstPart;
-    // Notify finished when the first part ends.
-    if (!errorOccurred())
-      setStatus(Cached);
-    // We notify clients and observers of finish in checkNotify() and
-    // updateImageAndClearBuffer(), respectively, and they will not be
-    // notified again in Resource::finish()/error().
-    checkNotify();
-    if (loader())
-      loader()->didFinishLoadingFirstPartInMultipart();
-  }
+bool ImageResourceContent::hasDevicePixelRatioHeaderValue() const {
+  return m_info->hasDevicePixelRatioHeaderValue();
 }
 
-void ImageResource::multipartDataReceived(const char* bytes, size_t size) {
-  DCHECK(m_multipartParser);
-  Resource::appendData(bytes, size);
+const ResourceResponse& ImageResourceContent::response() const {
+  return m_info->response();
 }
 
-bool ImageResource::isAccessAllowed(SecurityOrigin* securityOrigin) {
-  if (response().wasFetchedViaServiceWorker()) {
-    return response().serviceWorkerResponseType() !=
-           WebServiceWorkerResponseTypeOpaque;
-  }
-  if (!getImage()->currentFrameHasSingleSecurityOrigin())
-    return false;
-  if (passesAccessControlCheck(securityOrigin))
-    return true;
-  return !securityOrigin->taintsCanvas(response().url());
+const ResourceError& ImageResourceContent::resourceError() const {
+  return m_info->resourceError();
 }
 
 }  // namespace blink