Split ImageResourceClient into ResourceClient and ImageResourceObserver [1/2]

We are planning to move ResourceClient to on-heap, but LayoutObject (an
ImageResourceClient subclass) is hard to move to on-heap.

This series of CLs splits ImageResourceClient into
- ResourceClient (notified via Resource, to be moved to Oilpan heap) and
- ImageResourceObserver (notified via ImageObserver, to remain non-heap)
and makes LayoutObject to be ImageResourceObserver but not ResourceClient.

This is the [1/2] CL that
- Splits ImageResourceClient into ResourceClient and ImageResourceObserver,
- Makes LayoutObject and all of its subclasses (except for LayoutImage and its
  subclasses) to be ImageResourceObserver but not ResourceClient.

LayoutImage will be made non-ResourceClient by the [2/2] CL:
https://codereview.chromium.org/1728313003/.

Original CL: https://codereview.chromium.org/1697713002/ by Nate Chapin.

In addition to Nate's original CL (Patch Set 1), this CL:
- Fixes layout test (Patch Set 2).
- Reuses ResourceClientWalker to iterate ImageResourceObserver (Patch Set 3).
- Handles ResourceClient and ImageResourceObserver more similarly (Patch Set 4).
- Renames methods to reflect whether they are for both ResourceClient and
  ImageResourceObserver (Patch Set 6).

BUG=587663

Review URL: https://codereview.chromium.org/1706083002

Cr-Commit-Position: refs/heads/master@{#383425}

41 files changed, 284 insertions, 215 deletions

diff --git a/third_party/WebKit/Source/core/core.gypi b/third_party/WebKit/Source/core/core.gypi
index b993993..9a40587 100644
--- a/third_party/WebKit/Source/core/core.gypi
+++ b/third_party/WebKit/Source/core/core.gypi
@@ -1633,7 +1633,7 @@
             'fetch/RawResource.h',
             'fetch/Resource.cpp',
             'fetch/Resource.h',
-            'fetch/ResourceClientWalker.h',
+            'fetch/ResourceClientOrObserverWalker.h',
             'fetch/ResourceFetcher.cpp',
             'fetch/ResourceFetcher.h',
             'fetch/ResourceLoader.cpp',
@@ -3975,7 +3975,7 @@
             'fetch/FetchUtilsTest.cpp',
             'fetch/ImageResourceTest.cpp',
             'fetch/MemoryCacheTest.cpp',
-            'fetch/MockImageResourceClient.cpp',
+            'fetch/MockResourceClients.cpp',
             'fetch/MultipartImageResourceParserTest.cpp',
             'fetch/RawResourceTest.cpp',
             'fetch/ResourceFetcherTest.cpp',
diff --git a/third_party/WebKit/Source/core/css/CSSCrossfadeValue.cpp b/third_party/WebKit/Source/core/css/CSSCrossfadeValue.cpp
index 6eeb562..bf557f5 100644
--- a/third_party/WebKit/Source/core/css/CSSCrossfadeValue.cpp
+++ b/third_party/WebKit/Source/core/css/CSSCrossfadeValue.cpp
@@ -126,11 +126,11 @@ CSSCrossfadeValue::~CSSCrossfadeValue()
 void CSSCrossfadeValue::dispose()
 {
     if (m_cachedFromImage) {
-        m_cachedFromImage->removeClient(&m_crossfadeSubimageObserver);
+        m_cachedFromImage->removeObserver(&m_crossfadeSubimageObserver);
         m_cachedFromImage = nullptr;
     }
     if (m_cachedToImage) {
-        m_cachedToImage->removeClient(&m_crossfadeSubimageObserver);
+        m_cachedToImage->removeObserver(&m_crossfadeSubimageObserver);
         m_cachedToImage = nullptr;
     }
 }
@@ -208,16 +208,16 @@ void CSSCrossfadeValue::loadSubimages(Document* document)
 
     if (m_cachedFromImage != oldCachedFromImage) {
         if (oldCachedFromImage)
-            oldCachedFromImage->removeClient(&m_crossfadeSubimageObserver);
+            oldCachedFromImage->removeObserver(&m_crossfadeSubimageObserver);
         if (m_cachedFromImage)
-            m_cachedFromImage->addClient(&m_crossfadeSubimageObserver);
+            m_cachedFromImage->addObserver(&m_crossfadeSubimageObserver);
     }
 
     if (m_cachedToImage != oldCachedToImage) {
         if (oldCachedToImage)
-            oldCachedToImage->removeClient(&m_crossfadeSubimageObserver);
+            oldCachedToImage->removeObserver(&m_crossfadeSubimageObserver);
         if (m_cachedToImage)
-            m_cachedToImage->addClient(&m_crossfadeSubimageObserver);
+            m_cachedToImage->addObserver(&m_crossfadeSubimageObserver);
     }
 
     m_crossfadeSubimageObserver.setReady(true);
diff --git a/third_party/WebKit/Source/core/css/CSSCrossfadeValue.h b/third_party/WebKit/Source/core/css/CSSCrossfadeValue.h
index 8949409..9839551 100644
--- a/third_party/WebKit/Source/core/css/CSSCrossfadeValue.h
+++ b/third_party/WebKit/Source/core/css/CSSCrossfadeValue.h
@@ -30,7 +30,7 @@
 #include "core/css/CSSImageGeneratorValue.h"
 #include "core/css/CSSPrimitiveValue.h"
 #include "core/fetch/ImageResource.h"
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ImageResourceObserver.h"
 #include "platform/graphics/Image.h"
 
 namespace blink {
@@ -74,7 +74,7 @@ private:
 
     void dispose();
 
-    class CrossfadeSubimageObserverProxy final : public ImageResourceClient {
+    class CrossfadeSubimageObserverProxy final : public ImageResourceObserver {
         DISALLOW_NEW();
     public:
         explicit CrossfadeSubimageObserverProxy(CSSCrossfadeValue* ownerValue)
diff --git a/third_party/WebKit/Source/core/fetch/CSSStyleSheetResource.cpp b/third_party/WebKit/Source/core/fetch/CSSStyleSheetResource.cpp
index 5f1bf13..20bd626 100644
--- a/third_party/WebKit/Source/core/fetch/CSSStyleSheetResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/CSSStyleSheetResource.cpp
@@ -29,7 +29,7 @@
 #include "core/css/StyleSheetContents.h"
 #include "core/fetch/FetchRequest.h"
 #include "core/fetch/MemoryCache.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/StyleSheetResourceClient.h"
 #include "platform/SharedBuffer.h"
diff --git a/third_party/WebKit/Source/core/fetch/FontResource.cpp b/third_party/WebKit/Source/core/fetch/FontResource.cpp
index 73b1083..331c44e 100644
--- a/third_party/WebKit/Source/core/fetch/FontResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/FontResource.cpp
@@ -27,7 +27,7 @@
 #include "core/fetch/FontResource.h"
 
 #include "core/fetch/FetchRequest.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "platform/Histogram.h"
 #include "platform/SharedBuffer.h"
@@ -183,10 +183,10 @@ void FontResource::fontLoadLongLimitCallback(Timer<FontResource>*)
         client->fontLoadLongLimitExceeded(this);
 }
 
-void FontResource::allClientsRemoved()
+void FontResource::allClientsAndObserversRemoved()
 {
     m_fontData.clear();
-    Resource::allClientsRemoved();
+    Resource::allClientsAndObserversRemoved();
 }
 
 void FontResource::checkNotify()
diff --git a/third_party/WebKit/Source/core/fetch/FontResource.h b/third_party/WebKit/Source/core/fetch/FontResource.h
index 9702c5e..e2d542f 100644
--- a/third_party/WebKit/Source/core/fetch/FontResource.h
+++ b/third_party/WebKit/Source/core/fetch/FontResource.h
@@ -51,7 +51,7 @@ public:
 
     void didAddClient(ResourceClient*) override;
 
-    void allClientsRemoved() override;
+    void allClientsAndObserversRemoved() override;
     void beginLoadIfNeeded(ResourceFetcher* dl);
 
     bool loadScheduled() const { return getStatus() == LoadStartScheduled; }
diff --git a/third_party/WebKit/Source/core/fetch/ImageResource.cpp b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
index bb21c47..60911b1 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
@@ -23,10 +23,10 @@
 
 #include "core/fetch/ImageResource.h"
 
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ImageResourceObserver.h"
 #include "core/fetch/MemoryCache.h"
 #include "core/fetch/ResourceClient.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ResourceLoader.h"
 #include "core/svg/graphics/SVGImage.h"
@@ -41,6 +41,8 @@
 
 namespace blink {
 
+using ImageResourceObserverWalker = ResourceClientOrObserverWalker<ImageResourceObserver, ImageResourceObserver>;
+
 PassRefPtrWillBeRawPtr<ImageResource> ImageResource::fetch(FetchRequest& request, ResourceFetcher* fetcher)
 {
     if (request.resourceRequest().requestContext() == WebURLRequest::RequestContextUnspecified)
@@ -99,26 +101,44 @@ DEFINE_TRACE(ImageResource)
     MultipartImageResourceParser::Client::trace(visitor);
 }
 
-void ImageResource::didAddClient(ResourceClient* c)
+void ImageResource::addObserver(ImageResourceObserver* observer)
 {
+    willAddClientOrObserver();
+
+    m_observers.add(observer);
+
+    if (!m_revalidatingRequest.isNull())
+        return;
+
     if (m_data && !m_image && !errorOccurred()) {
         createImage();
         m_image->setData(m_data, true);
     }
 
-    ASSERT(ImageResourceClient::isExpectedType(c));
     if (m_image && !m_image->isNull())
-        static_cast<ImageResourceClient*>(c)->imageChanged(this);
-
-    Resource::didAddClient(c);
+        observer->imageChanged(this);
 }
 
-void ImageResource::didRemoveClient(ResourceClient* c)
+void ImageResource::removeObserver(ImageResourceObserver* observer)
 {
-    ASSERT(c);
-    ASSERT(ImageResourceClient::isExpectedType(c));
+    ASSERT(observer);
+    ASSERT(m_observers.contains(observer));
+    m_observers.remove(observer);
+    didRemoveClientOrObserver();
+}
 
-    Resource::didRemoveClient(c);
+ResourcePriority ImageResource::priorityFromObservers()
+{
+    ResourcePriority priority;
+    ImageResourceObserverWalker w(m_observers);
+    while (const auto* observer = w.next()) {
+        ResourcePriority nextPriority = observer->computeResourcePriority();
+        if (nextPriority.visibility == ResourcePriority::NotVisible)
+            continue;
+        priority.visibility = ResourcePriority::Visible;
+        priority.intraPriorityValue += nextPriority.intraPriorityValue;
+    }
+    return priority;
 }
 
 bool ImageResource::isSafeToUnlock() const
@@ -135,7 +155,7 @@ void ImageResource::destroyDecodedDataForFailedRevalidation()
 
 void ImageResource::destroyDecodedDataIfPossible()
 {
-    if (!hasClients() && !isLoading() && (!m_image || (m_image->hasOneRef() && m_image->isBitmapImage()))) {
+    if (!hasClientsOrObservers() && !isLoading() && (!m_image || (m_image->hasOneRef() && m_image->isBitmapImage()))) {
         m_image = nullptr;
         setDecodedSize(0);
     } else if (m_image && !errorOccurred()) {
@@ -143,13 +163,13 @@ void ImageResource::destroyDecodedDataIfPossible()
     }
 }
 
-void ImageResource::allClientsRemoved()
+void ImageResource::allClientsAndObserversRemoved()
 {
     if (m_image && !errorOccurred())
         m_image->resetAnimation();
     if (m_multipartParser)
         m_multipartParser->cancel();
-    Resource::allClientsRemoved();
+    Resource::allClientsAndObserversRemoved();
 }
 
 void ImageResource::appendData(const char* data, size_t length)
@@ -241,13 +261,10 @@ LayoutSize ImageResource::imageSize(RespectImageOrientationEnum shouldRespectIma
 
 void ImageResource::notifyObservers(const IntRect* changeRect)
 {
-    ResourceClientWalker<ImageResourceClient> w(m_clients);
-    while (ImageResourceClient* c = w.next())
-        c->imageChanged(this, changeRect);
-
-    ResourceClientWalker<ImageResourceClient> w2(m_finishedClients);
-    while (ImageResourceClient* c = w2.next())
-        c->imageChanged(this, changeRect);
+    ImageResourceObserverWalker w(m_observers);
+    while (auto* observer = w.next()) {
+        observer->imageChanged(this, changeRect);
+    }
 }
 
 void ImageResource::clear()
@@ -388,18 +405,11 @@ bool ImageResource::shouldPauseAnimation(const blink::Image* image)
     if (!image || image != m_image)
         return false;
 
-    ResourceClientWalker<ImageResourceClient> w(m_clients);
-    while (ImageResourceClient* c = w.next()) {
-        if (c->willRenderImage(this))
-            return false;
-    }
-
-    ResourceClientWalker<ImageResourceClient> w2(m_finishedClients);
-    while (ImageResourceClient* c = w2.next()) {
-        if (c->willRenderImage(this))
+    ImageResourceObserverWalker w(m_observers);
+    while (auto* observer = w.next()) {
+        if (observer->willRenderImage())
             return false;
     }
-
     return true;
 }
 
@@ -416,15 +426,9 @@ void ImageResource::updateImageAnimationPolicy()
         return;
 
     ImageAnimationPolicy newPolicy = ImageAnimationPolicyAllowed;
-    ResourceClientWalker<ImageResourceClient> w(m_clients);
-    while (ImageResourceClient* c = w.next()) {
-        if (c->getImageAnimationPolicy(this, newPolicy))
-            break;
-    }
-
-    ResourceClientWalker<ImageResourceClient> w2(m_finishedClients);
-    while (ImageResourceClient* c = w2.next()) {
-        if (c->getImageAnimationPolicy(this, newPolicy))
+    ImageResourceObserverWalker w(m_observers);
+    while (auto* observer = w.next()) {
+        if (observer->getImageAnimationPolicy(newPolicy))
             break;
     }
 
diff --git a/third_party/WebKit/Source/core/fetch/ImageResource.h b/third_party/WebKit/Source/core/fetch/ImageResource.h
index db8c6ab..74849d1 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResource.h
+++ b/third_party/WebKit/Source/core/fetch/ImageResource.h
@@ -35,19 +35,20 @@
 
 namespace blink {
 
-class ImageResourceClient;
 class FetchRequest;
-class ResourceFetcher;
 class FloatSize;
+class ImageResourceObserver;
 class Length;
 class MemoryCache;
+class ResourceClient;
+class ResourceFetcher;
 class SecurityOrigin;
 
 class CORE_EXPORT ImageResource final : public Resource, public ImageObserver, public MultipartImageResourceParser::Client {
     friend class MemoryCache;
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(ImageResource);
 public:
-    using ClientType = ImageResourceClient;
+    using ClientType = ResourceClient;
 
     static PassRefPtrWillBeRawPtr<ImageResource> fetch(FetchRequest&, ResourceFetcher*);
 
@@ -91,10 +92,13 @@ public:
     // the Lo-Fi state set to off and bypassing the cache.
     void reloadIfLoFi(ResourceFetcher*);
 
-    void didAddClient(ResourceClient*) override;
-    void didRemoveClient(ResourceClient*) override;
+    void addObserver(ImageResourceObserver*);
+    void removeObserver(ImageResourceObserver*);
+    bool hasClientsOrObservers() const override { return Resource::hasClientsOrObservers() || !m_observers.isEmpty(); }
+
+    ResourcePriority priorityFromObservers() override;
 
-    void allClientsRemoved() override;
+    void allClientsAndObserversRemoved() override;
 
     void appendData(const char*, size_t) override;
     void error(Resource::Status) override;
@@ -162,6 +166,7 @@ private:
     RefPtr<blink::Image> m_image;
     MultipartParsingState m_multipartParsingState = MultipartParsingState::WaitingForFirstPart;
     bool m_hasDevicePixelRatioHeaderValue;
+    HashCountedSet<ImageResourceObserver*> m_observers;
 };
 
 DEFINE_RESOURCE_TYPE_CASTS(Image);
diff --git a/third_party/WebKit/Source/core/fetch/ImageResourceClient.h b/third_party/WebKit/Source/core/fetch/ImageResourceObserver.h
index cc69a3d..9a002c4 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResourceClient.h
+++ b/third_party/WebKit/Source/core/fetch/ImageResourceObserver.h
@@ -20,23 +20,22 @@
     Boston, MA 02110-1301, USA.
 */
 
-#ifndef ImageResourceClient_h
-#define ImageResourceClient_h
+#ifndef ImageResourceObserver_h
+#define ImageResourceObserver_h
 
 #include "core/CoreExport.h"
-#include "core/fetch/ResourceClient.h"
 #include "platform/graphics/ImageAnimationPolicy.h"
+#include "platform/network/ResourceLoadPriority.h"
+#include "wtf/Forward.h"
 
 namespace blink {
 
 class ImageResource;
 class IntRect;
 
-class CORE_EXPORT ImageResourceClient : public ResourceClient {
+class CORE_EXPORT ImageResourceObserver {
 public:
-    ~ImageResourceClient() override {}
-    static bool isExpectedType(ResourceClient* client) { return client->getResourceClientType() == ImageType; }
-    ResourceClientType getResourceClientType() const final { return ImageType; }
+    virtual ~ImageResourceObserver() {}
 
     // Called whenever a frame of an image changes, either because we got more data from the network or
     // because we are animating. If not null, the IntRect is the changed rect of the image.
@@ -46,10 +45,17 @@ public:
     // can halt animation. Content nodes that hold image refs for example would not render the image,
     // but LayoutImages would (assuming they have visibility: visible and their layout tree isn't hidden
     // e.g., in the b/f cache or in a background tab).
-    virtual bool willRenderImage(ImageResource*) { return false; }
+    virtual bool willRenderImage() { return false; }
 
     // Called to get imageAnimation policy from settings
-    virtual bool getImageAnimationPolicy(ImageResource*, ImageAnimationPolicy&) { return false; }
+    virtual bool getImageAnimationPolicy(ImageAnimationPolicy&) { return false; }
+
+    virtual ResourcePriority computeResourcePriority() const { return ResourcePriority(); }
+
+    // Name for debugging, e.g. shown in memory-infra.
+    virtual String debugName() const = 0;
+
+    static bool isExpectedType(ImageResourceObserver*) { return true; }
 };
 
 } // namespace blink
diff --git a/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp b/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
index c3ecd53..4e7a570 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
@@ -30,9 +30,8 @@
 
 #include "core/fetch/ImageResource.h"
 
-#include "core/fetch/ImageResourceClient.h"
 #include "core/fetch/MemoryCache.h"
-#include "core/fetch/MockImageResourceClient.h"
+#include "core/fetch/MockResourceClients.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ResourceLoader.h"
 #include "core/fetch/UniqueIdentifier.h"
@@ -195,14 +194,14 @@ TEST(ImageResourceTest, DecodedDataRemainsWhileHasClients)
 
     // The prune comes when the ImageResource still has clients. The image should not be deleted.
     cachedImage->prune();
-    ASSERT_TRUE(cachedImage->hasClients());
+    ASSERT_TRUE(cachedImage->hasClientsOrObservers());
     ASSERT_TRUE(cachedImage->hasImage());
     ASSERT_FALSE(cachedImage->getImage()->isNull());
 
     // The ImageResource no longer has clients. The image should be deleted by prune.
     client.removeAsClient();
     cachedImage->prune();
-    ASSERT_FALSE(cachedImage->hasClients());
+    ASSERT_FALSE(cachedImage->hasClientsOrObservers());
     ASSERT_FALSE(cachedImage->hasImage());
     ASSERT_TRUE(cachedImage->getImage()->isNull());
 }
diff --git a/third_party/WebKit/Source/core/fetch/MemoryCache.cpp b/third_party/WebKit/Source/core/fetch/MemoryCache.cpp
index 4a9dfe0..059fe31 100644
--- a/third_party/WebKit/Source/core/fetch/MemoryCache.cpp
+++ b/third_party/WebKit/Source/core/fetch/MemoryCache.cpp
@@ -253,7 +253,7 @@ void MemoryCache::pruneLiveResources(PruneStrategy strategy)
     MemoryCacheEntry* current = m_liveDecodedResources.m_tail;
     while (current) {
         MemoryCacheEntry* previous = current->m_previousInLiveResourcesList;
-        ASSERT(current->m_resource->hasClients());
+        ASSERT(current->m_resource->hasClientsOrObservers());
         if (current->m_resource->isLoaded() && current->m_resource->decodedSize()) {
             // Check to see if the remaining resources are too new to prune.
             double elapsedTime = m_pruneFrameTimeStamp - current->m_lastDecodedAccessTime;
@@ -301,7 +301,7 @@ void MemoryCache::pruneDeadResources(PruneStrategy strategy)
             // TODO(leon.han@intel.com): We shouldn't be hitting the case
             // that current->m_resource is null here, would turn the case into
             // ASSERT(current->m_resource) after crbug.com/594644 got resolved.
-            if (current->m_resource && !current->m_resource->hasClients() && !current->m_resource->isPreloaded() && current->m_resource->isLoaded()) {
+            if (current->m_resource && !current->m_resource->hasClientsOrObservers() && !current->m_resource->isPreloaded() && current->m_resource->isLoaded()) {
                 // Destroy our decoded data. This will remove us from
                 // m_liveDecodedResources, and possibly move us to a different
                 // LRU list in m_allResources.
@@ -328,7 +328,7 @@ void MemoryCache::pruneDeadResources(PruneStrategy strategy)
             // TODO(leon.han@intel.com): We shouldn't be hitting the case
             // that current->m_resource is null here, would turn the case into
             // ASSERT(current->m_resource) after crbug.com/594644 got resolved.
-            if (current->m_resource && !current->m_resource->hasClients() && !current->m_resource->isPreloaded()) {
+            if (current->m_resource && !current->m_resource->hasClientsOrObservers() && !current->m_resource->isPreloaded()) {
                 evict(current);
                 if (targetSize && m_deadSize <= targetSize)
                     return;
@@ -540,7 +540,7 @@ void MemoryCache::update(Resource* resource, size_t oldSize, size_t newSize, boo
         insertInLRUList(entry, lruListFor(entry->m_accessCount, newSize));
 
     ptrdiff_t delta = newSize - oldSize;
-    if (resource->hasClients()) {
+    if (resource->hasClientsOrObservers()) {
         ASSERT(delta >= 0 || m_liveSize >= static_cast<size_t>(-delta) );
         m_liveSize += delta;
     } else {
@@ -556,7 +556,7 @@ void MemoryCache::updateDecodedResource(Resource* resource, UpdateReason reason)
         return;
 
     removeFromLiveDecodedResourcesList(entry);
-    if (resource->decodedSize() && resource->hasClients())
+    if (resource->decodedSize() && resource->hasClientsOrObservers())
         insertInLiveDecodedResourcesList(entry);
 
     if (reason != UpdateForAccess)
@@ -581,7 +581,7 @@ void MemoryCache::TypeStatistic::addResource(Resource* o)
     size_t pageSize = (o->encodedSize() + o->overheadSize() + 4095) & ~4095;
     count++;
     size += o->size();
-    liveSize += o->hasClients() ? o->size() : 0;
+    liveSize += o->hasClientsOrObservers() ? o->size() : 0;
     decodedSize += o->decodedSize();
     encodedSize += o->encodedSize();
     encodedSizeDuplicatedInDataURLs += o->url().protocolIsData() ? o->encodedSize() : 0;
@@ -772,8 +772,8 @@ void MemoryCache::dumpLRULists(bool includeLive) const
         MemoryCacheEntry* current = m_allResources[i].m_tail;
         while (current) {
             RefPtrWillBeRawPtr<Resource> currentResource = current->m_resource;
-            if (includeLive || !currentResource->hasClients())
-                printf("(%.1fK, %.1fK, %uA, %dR, %d); ", currentResource->decodedSize() / 1024.0f, (currentResource->encodedSize() + currentResource->overheadSize()) / 1024.0f, current->m_accessCount, currentResource->hasClients(), currentResource->isPurgeable());
+            if (includeLive || !currentResource->hasClientsOrObservers())
+                printf("(%.1fK, %.1fK, %uA, %dR, %d); ", currentResource->decodedSize() / 1024.0f, (currentResource->encodedSize() + currentResource->overheadSize()) / 1024.0f, current->m_accessCount, currentResource->hasClientsOrObservers(), currentResource->isPurgeable());
 
             current = current->m_previousInAllResourcesList;
         }
diff --git a/third_party/WebKit/Source/core/fetch/MemoryCacheTest.cpp b/third_party/WebKit/Source/core/fetch/MemoryCacheTest.cpp
index 57dcb78..efd29b4 100644
--- a/third_party/WebKit/Source/core/fetch/MemoryCacheTest.cpp
+++ b/third_party/WebKit/Source/core/fetch/MemoryCacheTest.cpp
@@ -30,7 +30,7 @@
 
 #include "core/fetch/MemoryCache.h"
 
-#include "core/fetch/MockImageResourceClient.h"
+#include "core/fetch/MockResourceClients.h"
 #include "core/fetch/RawResource.h"
 #include "platform/network/ResourceRequest.h"
 #include "platform/testing/UnitTestHelpers.h"
@@ -133,7 +133,7 @@ TEST_F(MemoryCacheTest, VeryLargeResourceAccounting)
     ASSERT_EQ(cachedResource->size(), memoryCache()->deadSize());
     ASSERT_EQ(0u, memoryCache()->liveSize());
 
-    MockImageResourceClient client(cachedResource);
+    MockResourceClient client(cachedResource);
     ASSERT_EQ(0u, memoryCache()->deadSize());
     ASSERT_EQ(cachedResource->size(), memoryCache()->liveSize());
 
@@ -237,7 +237,7 @@ static void TestLiveResourceEvictionAtEndOfTask(Resource* cachedDeadResource, Re
     const char data[6] = "abcde";
     cachedDeadResource->appendData(data, 3u);
     cachedDeadResource->finish();
-    MockImageResourceClient client(cachedLiveResource);
+    MockResourceClient client(cachedLiveResource);
     cachedLiveResource->appendData(data, 4u);
     cachedLiveResource->finish();
 
@@ -294,9 +294,9 @@ TEST_F(MemoryCacheTest, LiveResourceEvictionAtEndOfTask_MultipleResourceMaps)
 static void TestClientRemoval(Resource* resource1, Resource* resource2)
 {
     const char data[6] = "abcde";
-    MockImageResourceClient client1(resource1);
+    MockResourceClient client1(resource1);
     resource1->appendData(data, 4u);
-    MockImageResourceClient client2(resource2);
+    MockResourceClient client2(resource2);
     resource2->appendData(data, 4u);
 
     const unsigned minDeadCapacity = 0;
diff --git a/third_party/WebKit/Source/core/fetch/MockImageResourceClient.cpp b/third_party/WebKit/Source/core/fetch/MockResourceClients.cpp
index b3d9d15..1894dab 100644
--- a/third_party/WebKit/Source/core/fetch/MockImageResourceClient.cpp
+++ b/third_party/WebKit/Source/core/fetch/MockResourceClients.cpp
@@ -2,37 +2,59 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "core/fetch/MockImageResourceClient.h"
+#include "core/fetch/MockResourceClients.h"
 
 #include "core/fetch/ImageResource.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
-MockImageResourceClient::MockImageResourceClient(PassRefPtrWillBeRawPtr<Resource> resource)
+MockResourceClient::MockResourceClient(PassRefPtrWillBeRawPtr<Resource> resource)
     : m_resource(resource.get())
-    , m_imageChangedCount(0)
     , m_notifyFinishedCalled(false)
 {
     m_resource->addClient(this);
 }
 
-MockImageResourceClient::~MockImageResourceClient()
+MockResourceClient::~MockResourceClient()
 {
     if (m_resource)
         m_resource->removeClient(this);
 }
-
-void MockImageResourceClient::notifyFinished(Resource*)
+void MockResourceClient::notifyFinished(Resource*)
 {
     ASSERT_FALSE(m_notifyFinishedCalled);
     m_notifyFinishedCalled = true;
 }
 
-void MockImageResourceClient::removeAsClient()
+void MockResourceClient::removeAsClient()
 {
     m_resource->removeClient(this);
     m_resource = nullptr;
 }
 
+MockImageResourceClient::MockImageResourceClient(PassRefPtrWillBeRawPtr<ImageResource> resource)
+    : MockResourceClient(resource)
+    , m_imageChangedCount(0)
+{
+    toImageResource(m_resource.get())->addObserver(this);
+}
+
+MockImageResourceClient::~MockImageResourceClient()
+{
+    if (m_resource)
+        toImageResource(m_resource.get())->removeObserver(this);
+}
+
+void MockImageResourceClient::removeAsClient()
+{
+    toImageResource(m_resource.get())->removeObserver(this);
+    MockResourceClient::removeAsClient();
+}
+
+void MockImageResourceClient::imageChanged(ImageResource*, const IntRect*)
+{
+    m_imageChangedCount++;
+}
+
 } // namespace blink
diff --git a/third_party/WebKit/Source/core/fetch/MockImageResourceClient.h b/third_party/WebKit/Source/core/fetch/MockResourceClients.h
index b877a92..6fa5351 100644
--- a/third_party/WebKit/Source/core/fetch/MockImageResourceClient.h
+++ b/third_party/WebKit/Source/core/fetch/MockResourceClients.h
@@ -28,40 +28,50 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef MockImageResourceClient_h
-#define MockImageResourceClient_h
+#ifndef MockResourceClients_h
+#define MockResourceClients_h
 
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ImageResourceObserver.h"
 #include "core/fetch/Resource.h"
+#include "core/fetch/ResourceClient.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
-class MockImageResourceClient final : public ImageResourceClient {
+class MockResourceClient : public ResourceClient {
 public:
-    explicit MockImageResourceClient(const PassRefPtrWillBeRawPtr<Resource>);
+    explicit MockResourceClient(const PassRefPtrWillBeRawPtr<Resource>);
+    ~MockResourceClient() override;
+
+    void notifyFinished(Resource*) override;
+    String debugName() const override { return "MockResourceClient"; }
+    bool notifyFinishedCalled() const { return m_notifyFinishedCalled; }
+
+    virtual void removeAsClient();
+
+protected:
+    // TODO(Oilpan): properly trace when ResourceClient is on the heap.
+    RawPtrWillBeUntracedMember<Resource> m_resource;
+    bool m_notifyFinishedCalled;
+};
+
+class MockImageResourceClient final : public MockResourceClient, public ImageResourceObserver {
+public:
+    explicit MockImageResourceClient(const PassRefPtrWillBeRawPtr<ImageResource>);
     ~MockImageResourceClient() override;
 
-    void imageChanged(ImageResource*, const IntRect*) override
-    {
-        m_imageChangedCount++;
-    }
+    void imageChanged(ImageResource*, const IntRect*) override;
 
-    void notifyFinished(Resource*) override;
     String debugName() const override { return "MockImageResourceClient"; }
 
-    int imageChangedCount() const { return m_imageChangedCount; }
-    bool notifyFinishedCalled() const { return m_notifyFinishedCalled; }
+    void removeAsClient() override;
 
-    void removeAsClient();
+    int imageChangedCount() const { return m_imageChangedCount; }
 
 private:
-    // TODO(Oilpan): properly trace when ImageResourceClient is on the heap.
-    RawPtrWillBeUntracedMember<Resource> m_resource;
     int m_imageChangedCount;
-    bool m_notifyFinishedCalled;
 };
 
 } // namespace blink
 
-#endif // MockImageResourceClient_h
+#endif // MockResourceClients_h
diff --git a/third_party/WebKit/Source/core/fetch/RawResource.cpp b/third_party/WebKit/Source/core/fetch/RawResource.cpp
index 39c9ef9..a2f924d 100644
--- a/third_party/WebKit/Source/core/fetch/RawResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/RawResource.cpp
@@ -27,7 +27,7 @@
 
 #include "core/fetch/FetchRequest.h"
 #include "core/fetch/MemoryCache.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ResourceLoader.h"
 
diff --git a/third_party/WebKit/Source/core/fetch/RawResourceTest.cpp b/third_party/WebKit/Source/core/fetch/RawResourceTest.cpp
index 9496674..1b7aab2 100644
--- a/third_party/WebKit/Source/core/fetch/RawResourceTest.cpp
+++ b/third_party/WebKit/Source/core/fetch/RawResourceTest.cpp
@@ -30,9 +30,7 @@
 
 #include "core/fetch/RawResource.h"
 
-#include "core/fetch/ImageResourceClient.h"
 #include "core/fetch/MemoryCache.h"
-#include "core/fetch/MockImageResourceClient.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "platform/SharedBuffer.h"
 #include "platform/testing/UnitTestHelpers.h"
@@ -138,7 +136,7 @@ TEST(RawResourceTest, RevalidationSucceeded)
     memoryCache()->remove(resource.get());
 
     resource->removeClient(client.get());
-    EXPECT_FALSE(resource->hasClients());
+    EXPECT_FALSE(resource->hasClientsOrObservers());
     EXPECT_FALSE(client->called());
     EXPECT_EQ("abcd", String(client->data().data(), client->data().size()));
 }
@@ -168,7 +166,7 @@ TEST(RawResourceTest, RevalidationSucceededForResourceWithoutBody)
     memoryCache()->remove(resource.get());
 
     resource->removeClient(client.get());
-    EXPECT_FALSE(resource->hasClients());
+    EXPECT_FALSE(resource->hasClientsOrObservers());
     EXPECT_FALSE(client->called());
     EXPECT_EQ(0u, client->data().size());
 }
@@ -190,7 +188,7 @@ TEST(RawResourceTest, AddClientDuringCallback)
     testing::runPendingTasks();
     raw->removeClient(addingClient.get());
     EXPECT_FALSE(dummyClient->called());
-    EXPECT_FALSE(raw->hasClients());
+    EXPECT_FALSE(raw->hasClientsOrObservers());
 }
 
 // This client removes another client when notified.
@@ -228,7 +226,7 @@ TEST(RawResourceTest, RemoveClientDuringCallback)
     raw->addClient(dummyClient.get());
     raw->addClient(removingClient.get());
     testing::runPendingTasks();
-    EXPECT_FALSE(raw->hasClients());
+    EXPECT_FALSE(raw->hasClientsOrObservers());
 }
 
 } // namespace blink
diff --git a/third_party/WebKit/Source/core/fetch/Resource.cpp b/third_party/WebKit/Source/core/fetch/Resource.cpp
index 05d2e40..a311e3f 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.cpp
+++ b/third_party/WebKit/Source/core/fetch/Resource.cpp
@@ -28,7 +28,7 @@
 #include "core/fetch/FetchInitiatorTypeNames.h"
 #include "core/fetch/MemoryCache.h"
 #include "core/fetch/ResourceClient.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ResourceLoader.h"
 #include "core/inspector/InspectorInstrumentation.h"
@@ -426,7 +426,7 @@ bool Resource::unlock()
     if (!m_data->isLocked())
         return true;
 
-    if (!memoryCache()->contains(this) || hasClients() || !m_revalidatingRequest.isNull() || !m_loadFinishTime || !isSafeToUnlock())
+    if (!memoryCache()->contains(this) || hasClientsOrObservers() || !m_revalidatingRequest.isNull() || !m_loadFinishTime || !isSafeToUnlock())
         return false;
 
     m_data->unlock();
@@ -506,7 +506,7 @@ WeakPtrWillBeRawPtr<Resource> Resource::asWeakPtr()
 String Resource::reasonNotDeletable() const
 {
     StringBuilder builder;
-    if (hasClients()) {
+    if (hasClientsOrObservers()) {
         builder.append("hasClients(");
         builder.appendNumber(m_clients.size());
         if (!m_clientsAwaitingCallback.isEmpty()) {
@@ -581,10 +581,9 @@ static bool shouldSendCachedDataSynchronouslyForType(Resource::Type type)
     return false;
 }
 
-void Resource::addClient(ResourceClient* client)
+void Resource::willAddClientOrObserver()
 {
     ASSERT(!isPurgeable());
-
     if (m_preloadResult == PreloadNotReferenced) {
         if (isLoaded())
             m_preloadResult = PreloadReferencedWhileComplete;
@@ -593,8 +592,13 @@ void Resource::addClient(ResourceClient* client)
         else
             m_preloadResult = PreloadReferenced;
     }
-    if (!hasClients())
+    if (!hasClientsOrObservers())
         memoryCache()->makeLive(this);
+}
+
+void Resource::addClient(ResourceClient* client)
+{
+    willAddClientOrObserver();
 
     if (!m_revalidatingRequest.isNull()) {
         m_clients.add(client);
@@ -623,15 +627,19 @@ void Resource::removeClient(ResourceClient* client)
     else
         m_clients.remove(client);
 
-    didRemoveClient(client);
-
     if (m_clientsAwaitingCallback.isEmpty())
         ResourceCallback::callbackHandler()->cancel(this);
 
-    if (!hasClients()) {
+    didRemoveClientOrObserver();
+    // This object may be dead here.
+}
+
+void Resource::didRemoveClientOrObserver()
+{
+    if (!hasClientsOrObservers()) {
         RefPtrWillBeRawPtr<Resource> protect(this);
         memoryCache()->makeDead(this);
-        allClientsRemoved();
+        allClientsAndObserversRemoved();
 
         // RFC2616 14.9.2:
         // "no-store: ... MUST make a best-effort attempt to remove the information from volatile storage as promptly as possible"
@@ -647,7 +655,7 @@ void Resource::removeClient(ResourceClient* client)
     // This object may be dead here.
 }
 
-void Resource::allClientsRemoved()
+void Resource::allClientsAndObserversRemoved()
 {
     if (!m_loader)
         return;
@@ -662,7 +670,7 @@ void Resource::allClientsRemoved()
 void Resource::cancelTimerFired(Timer<Resource>* timer)
 {
     ASSERT_UNUSED(timer, timer == &m_cancelTimer);
-    if (hasClients() || !m_loader)
+    if (hasClientsOrObservers() || !m_loader)
         return;
     RefPtrWillBeRawPtr<Resource> protect(this);
     m_loader->cancelIfNotFinishing();
@@ -877,7 +885,7 @@ bool Resource::lock()
     if (m_data->isLocked())
         return true;
 
-    ASSERT(!hasClients());
+    ASSERT(!hasClientsOrObservers());
 
     // If locking fails, our buffer has been purged. There's no point
     // in leaving a purged resource in MemoryCache.
@@ -903,20 +911,6 @@ void Resource::didChangePriority(ResourceLoadPriority loadPriority, int intraPri
         m_loader->didChangePriority(loadPriority, intraPriorityValue);
 }
 
-ResourcePriority Resource::priorityFromClients()
-{
-    ResourcePriority priority;
-    ResourceClientWalker<ResourceClient> walker(m_clients);
-    while (ResourceClient* c = walker.next()) {
-        ResourcePriority nextPriority = c->computeResourcePriority();
-        if (nextPriority.visibility == ResourcePriority::NotVisible)
-            continue;
-        priority.visibility = ResourcePriority::Visible;
-        priority.intraPriorityValue += nextPriority.intraPriorityValue;
-    }
-    return priority;
-}
-
 Resource::ResourceCallback* Resource::ResourceCallback::callbackHandler()
 {
     // Oilpan + LSan: as the callbackHandler() singleton is used by Resource
diff --git a/third_party/WebKit/Source/core/fetch/Resource.h b/third_party/WebKit/Source/core/fetch/Resource.h
index 68d1c6b..d6fb851 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.h
+++ b/third_party/WebKit/Source/core/fetch/Resource.h
@@ -127,11 +127,11 @@ public:
     ResourceLoaderOptions& mutableOptions() { return m_options; }
 
     void didChangePriority(ResourceLoadPriority, int intraPriorityValue);
-    ResourcePriority priorityFromClients();
+    virtual ResourcePriority priorityFromObservers() { return ResourcePriority(); }
 
     void addClient(ResourceClient*);
     void removeClient(ResourceClient*);
-    bool hasClients() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty() || !m_finishedClients.isEmpty(); }
+    virtual bool hasClientsOrObservers() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty() || !m_finishedClients.isEmpty(); }
 
     enum PreloadResult {
         PreloadNotReferenced,
@@ -141,10 +141,6 @@ public:
     };
     PreloadResult getPreloadResult() const { return static_cast<PreloadResult>(m_preloadResult); }
 
-    virtual void didAddClient(ResourceClient*);
-    virtual void didRemoveClient(ResourceClient*) { }
-    virtual void allClientsRemoved();
-
     unsigned count() const { return m_clients.size(); }
 
     Status getStatus() const { return static_cast<Status>(m_status); }
@@ -266,6 +262,13 @@ protected:
 
     void finishPendingClients();
 
+    virtual void didAddClient(ResourceClient*);
+    void willAddClientOrObserver();
+
+    // |this| object may be dead after didRemoveClientOrObserver().
+    void didRemoveClientOrObserver();
+    virtual void allClientsAndObserversRemoved();
+
     HashCountedSet<ResourceClient*> m_clients;
     HashCountedSet<ResourceClient*> m_clientsAwaitingCallback;
     HashCountedSet<ResourceClient*> m_finishedClients;
diff --git a/third_party/WebKit/Source/core/fetch/ResourceClient.h b/third_party/WebKit/Source/core/fetch/ResourceClient.h
index 41fe1bc..545886d 100644
--- a/third_party/WebKit/Source/core/fetch/ResourceClient.h
+++ b/third_party/WebKit/Source/core/fetch/ResourceClient.h
@@ -26,7 +26,6 @@
 #define ResourceClient_h
 
 #include "core/CoreExport.h"
-#include "platform/network/ResourceLoadPriority.h"
 #include "wtf/Forward.h"
 #include "wtf/text/WTFString.h"
 
@@ -37,7 +36,6 @@ class CORE_EXPORT ResourceClient {
 public:
     enum ResourceClientType {
         BaseResourceType,
-        ImageType,
         FontType,
         StyleSheetType,
         DocumentType,
@@ -51,8 +49,6 @@ public:
     static bool isExpectedType(ResourceClient*) { return true; }
     virtual ResourceClientType getResourceClientType() const { return BaseResourceType; }
 
-    virtual ResourcePriority computeResourcePriority() const { return ResourcePriority(); }
-
     // Name for debugging, e.g. shown in memory-infra.
     virtual String debugName() const = 0;
 
diff --git a/third_party/WebKit/Source/core/fetch/ResourceClientWalker.h b/third_party/WebKit/Source/core/fetch/ResourceClientOrObserverWalker.h
index 0dbbc23..24f5504 100644
--- a/third_party/WebKit/Source/core/fetch/ResourceClientWalker.h
+++ b/third_party/WebKit/Source/core/fetch/ResourceClientOrObserverWalker.h
@@ -22,8 +22,8 @@
     pages from the web. It has a memory cache for these objects.
 */
 
-#ifndef ResourceClientWalker_h
-#define ResourceClientWalker_h
+#ifndef ResourceClientOrObserverWalker_h
+#define ResourceClientOrObserverWalker_h
 
 #include "core/fetch/ResourceClient.h"
 #include "wtf/Allocator.h"
@@ -34,10 +34,13 @@ namespace blink {
 
 // Call this "walker" instead of iterator so people won't expect Qt or STL-style iterator interface.
 // Just keep calling next() on this. It's safe from deletions of items.
-template<typename T> class ResourceClientWalker {
+// ClientOrObserver is either ResourceClient or ImageResourceObserver, so that
+// this walker can be used both for ResourceClient and ImageResourceObserver.
+template<typename ClientOrObserver, typename T>
+class ResourceClientOrObserverWalker {
     STACK_ALLOCATED();
 public:
-    ResourceClientWalker(const HashCountedSet<ResourceClient*>& set)
+    explicit ResourceClientOrObserverWalker(const HashCountedSet<ClientOrObserver*>& set)
         : m_clientSet(set), m_clientVector(set.size()), m_index(0)
     {
         size_t clientIndex = 0;
@@ -49,7 +52,7 @@ public:
     {
         size_t size = m_clientVector.size();
         while (m_index < size) {
-            ResourceClient* next = m_clientVector[m_index++];
+            ClientOrObserver* next = m_clientVector[m_index++];
             if (m_clientSet.contains(next)) {
                 ASSERT(T::isExpectedType(next));
                 return static_cast<T*>(next);
@@ -59,11 +62,18 @@ public:
         return 0;
     }
 private:
-    const HashCountedSet<ResourceClient*>& m_clientSet;
-    Vector<ResourceClient*> m_clientVector;
+    const HashCountedSet<ClientOrObserver*>& m_clientSet;
+    Vector<ClientOrObserver*> m_clientVector;
     size_t m_index;
 };
 
+template<typename T>
+struct ResourceClientWalker : public ResourceClientOrObserverWalker<ResourceClient, T> {
+public:
+    explicit ResourceClientWalker(const HashCountedSet<ResourceClient*>& set)
+        : ResourceClientOrObserverWalker<ResourceClient, T>(set) { }
+};
+
 } // namespace blink
 
 #endif
diff --git a/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp b/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
index a5cc982..010832c 100644
--- a/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
+++ b/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
@@ -391,7 +391,7 @@ void ResourceFetcher::updateMemoryCacheStats(Resource* resource, RevalidationPol
     // would be dead if MemoryCache holds weak references to Resource).
     // Currently we check references to Resource from ResourceClient and
     // |m_preloads| only, because they are major sources of references.
-    if (resource && !resource->hasClients() && (!m_preloads || !m_preloads->contains(resource))) {
+    if (resource && !resource->hasClientsOrObservers() && (!m_preloads || !m_preloads->contains(resource))) {
         DEFINE_RESOURCE_HISTOGRAM("Dead.");
     }
 }
@@ -470,7 +470,7 @@ PassRefPtrWillBeRawPtr<Resource> ResourceFetcher::requestResource(FetchRequest&
         return nullptr;
     }
 
-    if (!resource->hasClients())
+    if (!resource->hasClientsOrObservers())
         m_deadStatsRecorder.update(policy);
 
     if (policy != Use)
@@ -1089,7 +1089,7 @@ void ResourceFetcher::updateAllImageResourcePriorities()
         if (!resource->isImage())
             continue;
 
-        ResourcePriority resourcePriority = resource->priorityFromClients();
+        ResourcePriority resourcePriority = resource->priorityFromObservers();
         ResourceLoadPriority resourceLoadPriority = loadPriority(Resource::Image, FetchRequest(resource->resourceRequest(), FetchInitiatorInfo()), resourcePriority.visibility);
         if (resourceLoadPriority == resource->resourceRequest().priority())
             continue;
diff --git a/third_party/WebKit/Source/core/fetch/ScriptResource.cpp b/third_party/WebKit/Source/core/fetch/ScriptResource.cpp
index 504192d..261454f 100644
--- a/third_party/WebKit/Source/core/fetch/ScriptResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/ScriptResource.cpp
@@ -28,7 +28,7 @@
 
 #include "core/fetch/FetchRequest.h"
 #include "core/fetch/IntegrityMetadata.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "platform/MIMETypeRegistry.h"
 #include "platform/SharedBuffer.h"
diff --git a/third_party/WebKit/Source/core/fetch/XSLStyleSheetResource.cpp b/third_party/WebKit/Source/core/fetch/XSLStyleSheetResource.cpp
index 82f5f94..9d77f22 100644
--- a/third_party/WebKit/Source/core/fetch/XSLStyleSheetResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/XSLStyleSheetResource.cpp
@@ -27,7 +27,7 @@
 #include "core/fetch/XSLStyleSheetResource.h"
 
 #include "core/fetch/FetchRequest.h"
-#include "core/fetch/ResourceClientWalker.h"
+#include "core/fetch/ResourceClientOrObserverWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/StyleSheetResourceClient.h"
 #include "platform/RuntimeEnabledFeatures.h"
diff --git a/third_party/WebKit/Source/core/frame/ImageBitmapTest.cpp b/third_party/WebKit/Source/core/frame/ImageBitmapTest.cpp
index 03f6bbd..68c9f93 100644
--- a/third_party/WebKit/Source/core/frame/ImageBitmapTest.cpp
+++ b/third_party/WebKit/Source/core/frame/ImageBitmapTest.cpp
@@ -35,7 +35,7 @@
 #include "core/dom/Document.h"
 #include "core/fetch/ImageResource.h"
 #include "core/fetch/MemoryCache.h"
-#include "core/fetch/MockImageResourceClient.h"
+#include "core/fetch/MockResourceClients.h"
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLImageElement.h"
 #include "core/html/HTMLVideoElement.h"
diff --git a/third_party/WebKit/Source/core/layout/LayoutImage.cpp b/third_party/WebKit/Source/core/layout/LayoutImage.cpp
index ddef161..bb23422 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImage.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutImage.cpp
@@ -89,7 +89,7 @@ void LayoutImage::setImageResource(PassOwnPtrWillBeRawPtr<LayoutImageResource> i
 {
     ASSERT(!m_imageResource);
     m_imageResource = imageResource;
-    m_imageResource->initialize(this);
+    m_imageResource->initialize(this, this);
 }
 
 void LayoutImage::imageChanged(WrappedImagePtr newImage, const IntRect* rect)
diff --git a/third_party/WebKit/Source/core/layout/LayoutImage.h b/third_party/WebKit/Source/core/layout/LayoutImage.h
index b162c7e..c81ed4e 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImage.h
+++ b/third_party/WebKit/Source/core/layout/LayoutImage.h
@@ -26,6 +26,7 @@
 #define LayoutImage_h
 
 #include "core/CoreExport.h"
+#include "core/fetch/ResourceClient.h"
 #include "core/layout/LayoutImageResource.h"
 #include "core/layout/LayoutReplaced.h"
 
@@ -43,7 +44,7 @@ class HTMLMapElement;
 //
 // The class is image type agnostic as it only manipulates decoded images.
 // See LayoutImageResource that holds this image.
-class CORE_EXPORT LayoutImage : public LayoutReplaced {
+class CORE_EXPORT LayoutImage : public LayoutReplaced, public ResourceClient {
 public:
     // These are the paddings to use when displaying either alt text or an image.
     static const unsigned short paddingWidth = 4;
@@ -77,6 +78,7 @@ public:
     }
 
     const char* name() const override { return "LayoutImage"; }
+    String debugName() const final { return LayoutObject::debugName(); }
 
 protected:
     bool needsPreferredWidthsRecalculation() const final;
diff --git a/third_party/WebKit/Source/core/layout/LayoutImageResource.cpp b/third_party/WebKit/Source/core/layout/LayoutImageResource.cpp
index a873c99..ed4aab3 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImageResource.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutImageResource.cpp
@@ -36,6 +36,7 @@ namespace blink {
 LayoutImageResource::LayoutImageResource()
     : m_layoutObject(nullptr)
     , m_cachedImage(nullptr)
+    , m_client(nullptr)
 {
 }
 
@@ -43,19 +44,23 @@ LayoutImageResource::~LayoutImageResource()
 {
 }
 
-void LayoutImageResource::initialize(LayoutObject* layoutObject)
+void LayoutImageResource::initialize(LayoutObject* layoutObject, ResourceClient* client)
 {
     ASSERT(!m_layoutObject);
     ASSERT(layoutObject);
     m_layoutObject = layoutObject;
+    m_client = client;
 }
 
 void LayoutImageResource::shutdown()
 {
     ASSERT(m_layoutObject);
 
-    if (m_cachedImage)
-        m_cachedImage->removeClient(m_layoutObject);
+    if (!m_cachedImage)
+        return;
+    if (m_client)
+        m_cachedImage->removeClient(m_client);
+    m_cachedImage->removeObserver(m_layoutObject);
 }
 
 void LayoutImageResource::setImageResource(ImageResource* newImage)
@@ -65,11 +70,16 @@ void LayoutImageResource::setImageResource(ImageResource* newImage)
     if (m_cachedImage == newImage)
         return;
 
-    if (m_cachedImage)
-        m_cachedImage->removeClient(m_layoutObject);
+    if (m_cachedImage) {
+        if (m_client)
+            m_cachedImage->removeClient(m_client);
+        m_cachedImage->removeObserver(m_layoutObject);
+    }
     m_cachedImage = newImage;
     if (m_cachedImage) {
-        m_cachedImage->addClient(m_layoutObject);
+        if (m_client)
+            m_cachedImage->addClient(m_client);
+        m_cachedImage->addObserver(m_layoutObject);
         if (m_cachedImage->errorOccurred())
             m_layoutObject->imageChanged(m_cachedImage.get());
     } else {
diff --git a/third_party/WebKit/Source/core/layout/LayoutImageResource.h b/third_party/WebKit/Source/core/layout/LayoutImageResource.h
index 9680c5a..9b87daf 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImageResource.h
+++ b/third_party/WebKit/Source/core/layout/LayoutImageResource.h
@@ -44,7 +44,7 @@ public:
         return adoptPtrWillBeNoop(new LayoutImageResource);
     }
 
-    virtual void initialize(LayoutObject*);
+    virtual void initialize(LayoutObject*, ResourceClient*);
     virtual void shutdown();
 
     void setImageResource(ImageResource*);
@@ -69,6 +69,7 @@ protected:
     LayoutImageResource();
     LayoutObject* m_layoutObject;
     RefPtrWillBeMember<ImageResource> m_cachedImage;
+    ResourceClient* m_client;
 };
 
 } // namespace blink
diff --git a/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.cpp b/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.cpp
index 390a214..017015c 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.cpp
@@ -44,9 +44,9 @@ LayoutImageResourceStyleImage::~LayoutImageResourceStyleImage()
     ASSERT(!m_cachedImage);
 }
 
-void LayoutImageResourceStyleImage::initialize(LayoutObject* layoutObject)
+void LayoutImageResourceStyleImage::initialize(LayoutObject* layoutObject, ResourceClient* client)
 {
-    LayoutImageResource::initialize(layoutObject);
+    LayoutImageResource::initialize(layoutObject, client);
 
     if (m_styleImage->isImageResource())
         m_cachedImage = toStyleFetchedImage(m_styleImage)->cachedImage();
diff --git a/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.h b/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.h
index 0cc4051..9ef29b1 100644
--- a/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.h
+++ b/third_party/WebKit/Source/core/layout/LayoutImageResourceStyleImage.h
@@ -42,7 +42,7 @@ public:
     {
         return adoptPtrWillBeNoop(new LayoutImageResourceStyleImage(styleImage));
     }
-    void initialize(LayoutObject*) override;
+    void initialize(LayoutObject*, ResourceClient*) override;
     void shutdown() override;
 
     bool hasImage() const override { return true; }
diff --git a/third_party/WebKit/Source/core/layout/LayoutObject.cpp b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
index b2d442b..ebd750e 100644
--- a/third_party/WebKit/Source/core/layout/LayoutObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
@@ -245,8 +245,7 @@ static WTF::RefCountedLeakCounter& layoutObjectCounter()
 #endif
 
 LayoutObject::LayoutObject(Node* node)
-    : ImageResourceClient()
-    , m_style(nullptr)
+    : m_style(nullptr)
     , m_node(node)
     , m_parent(nullptr)
     , m_previous(nullptr)
@@ -3221,7 +3220,7 @@ void LayoutObject::addAnnotatedRegions(Vector<AnnotatedRegionValue>& regions)
     regions.append(region);
 }
 
-bool LayoutObject::willRenderImage(ImageResource*)
+bool LayoutObject::willRenderImage()
 {
     // Without visibility we won't render (and therefore don't care about animation).
     if (style()->visibility() != VISIBLE)
@@ -3236,7 +3235,7 @@ bool LayoutObject::willRenderImage(ImageResource*)
     return document().view()->isVisible();
 }
 
-bool LayoutObject::getImageAnimationPolicy(ImageResource*, ImageAnimationPolicy& policy)
+bool LayoutObject::getImageAnimationPolicy(ImageAnimationPolicy& policy)
 {
     if (!document().settings())
         return false;
diff --git a/third_party/WebKit/Source/core/layout/LayoutObject.h b/third_party/WebKit/Source/core/layout/LayoutObject.h
index 47360a2..61d5f92 100644
--- a/third_party/WebKit/Source/core/layout/LayoutObject.h
+++ b/third_party/WebKit/Source/core/layout/LayoutObject.h
@@ -31,7 +31,7 @@
 #include "core/dom/DocumentLifecycle.h"
 #include "core/dom/Element.h"
 #include "core/editing/PositionWithAffinity.h"
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ImageResourceObserver.h"
 #include "core/html/HTMLElement.h"
 #include "core/inspector/InspectorTraceEvents.h"
 #include "core/layout/HitTestRequest.h"
@@ -155,7 +155,7 @@ const int showTreeCharacterOffset = 39;
 // storage for children. Descendant classes that do allow children have to have a LayoutObjectChildList
 // member that stores the actual children and override virtualChildren().
 //
-// LayoutObject is an ImageResourceClient, which means that it gets notified when associated images
+// LayoutObject is an ImageResourceObserver, which means that it gets notified when associated images
 // are changed. This is used for 2 main use cases:
 // - reply to 'background-image' as we need to invalidate the background in this case.
 //   (See https://drafts.csswg.org/css-backgrounds-3/#the-background-image)
@@ -209,7 +209,7 @@ const int showTreeCharacterOffset = 39;
 // preferredLogicalWidthsDirty.
 //
 // See the individual getters below for more details about what each width is.
-class CORE_EXPORT LayoutObject : public ImageResourceClient, public DisplayItemClient {
+class CORE_EXPORT LayoutObject : public ImageResourceObserver, public DisplayItemClient {
     friend class LayoutObjectChildList;
     WTF_MAKE_NONCOPYABLE(LayoutObject);
 public:
@@ -227,7 +227,7 @@ public:
 
     // DisplayItemClient methods.
     LayoutRect visualRect() const override;
-    String debugName() const final;
+    String debugName() const override;
 
     LayoutObject* parent() const { return m_parent; }
     bool isDescendantOf(const LayoutObject*) const;
@@ -1225,10 +1225,10 @@ public:
 
     virtual int previousOffsetForBackwardDeletion(int current) const;
 
-    // ImageResourceClient override.
+    // ImageResourceObserver override.
     void imageChanged(ImageResource*, const IntRect* = nullptr) final;
-    bool willRenderImage(ImageResource*) final;
-    bool getImageAnimationPolicy(ImageResource*, ImageAnimationPolicy&) final;
+    bool willRenderImage() final;
+    bool getImageAnimationPolicy(ImageAnimationPolicy&) final;
 
     // Sub-classes that have an associated image need to override this function
     // to get notified of any image change.
diff --git a/third_party/WebKit/Source/core/layout/svg/LayoutSVGImage.cpp b/third_party/WebKit/Source/core/layout/svg/LayoutSVGImage.cpp
index ccb9c17..5a8bf3a 100644
--- a/third_party/WebKit/Source/core/layout/svg/LayoutSVGImage.cpp
+++ b/third_party/WebKit/Source/core/layout/svg/LayoutSVGImage.cpp
@@ -47,7 +47,7 @@ LayoutSVGImage::LayoutSVGImage(SVGImageElement* impl)
     , m_needsTransformUpdate(true)
     , m_imageResource(LayoutImageResource::create())
 {
-    m_imageResource->initialize(this);
+    m_imageResource->initialize(this, nullptr);
 }
 
 LayoutSVGImage::~LayoutSVGImage()
diff --git a/third_party/WebKit/Source/core/loader/ImageLoader.cpp b/third_party/WebKit/Source/core/loader/ImageLoader.cpp
index ad037d8..4c1b72a 100644
--- a/third_party/WebKit/Source/core/loader/ImageLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/ImageLoader.cpp
@@ -181,6 +181,7 @@ void ImageLoader::dispose()
 
     if (m_image) {
         m_image->removeClient(this);
+        m_image->removeObserver(this);
         m_image = nullptr;
     }
 
@@ -225,10 +226,14 @@ void ImageLoader::setImageWithoutConsideringPendingLoadEvent(ImageResource* newI
             m_hasPendingErrorEvent = false;
         }
         m_imageComplete = true;
-        if (newImage)
+        if (newImage) {
             newImage->addClient(this);
-        if (oldImage)
+            newImage->addObserver(this);
+        }
+        if (oldImage) {
             oldImage->removeClient(this);
+            oldImage->removeObserver(this);
+        }
     }
 
     if (LayoutImageResource* imageResource = layoutImageResource())
@@ -367,11 +372,14 @@ void ImageLoader::doUpdateFromElement(BypassMainWorldBehavior bypassBehavior, Up
         updateLayoutObject();
         // If newImage exists and is cached, addClient() will result in the load event
         // being queued to fire. Ensure this happens after beforeload is dispatched.
-        if (newImage)
+        if (newImage) {
             newImage->addClient(this);
-
-        if (oldImage)
+            newImage->addObserver(this);
+        }
+        if (oldImage) {
             oldImage->removeClient(this);
+            oldImage->removeObserver(this);
+        }
     }
 
     if (LayoutImageResource* imageResource = layoutImageResource())
@@ -409,8 +417,10 @@ void ImageLoader::updateFromElement(UpdateFromElementBehavior updateBehavior, Re
     // an asynchronous load completes.
     if (imageSourceURL.isEmpty()) {
         ImageResource* image = m_image.get();
-        if (image)
+        if (image) {
             image->removeClient(this);
+            image->removeObserver(this);
+        }
         m_image = nullptr;
     }
 
@@ -605,7 +615,7 @@ void ImageLoader::dispatchPendingErrorEvent()
     updatedHasPendingEvent();
 }
 
-bool ImageLoader::getImageAnimationPolicy(ImageResource*, ImageAnimationPolicy& policy)
+bool ImageLoader::getImageAnimationPolicy(ImageAnimationPolicy& policy)
 {
     if (!element()->document().settings())
         return false;
diff --git a/third_party/WebKit/Source/core/loader/ImageLoader.h b/third_party/WebKit/Source/core/loader/ImageLoader.h
index 30ad783..abb6414 100644
--- a/third_party/WebKit/Source/core/loader/ImageLoader.h
+++ b/third_party/WebKit/Source/core/loader/ImageLoader.h
@@ -25,7 +25,8 @@
 
 #include "core/CoreExport.h"
 #include "core/fetch/ImageResource.h"
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ImageResourceObserver.h"
+#include "core/fetch/ResourceClient.h"
 #include "platform/heap/Handle.h"
 #include "wtf/HashSet.h"
 #include "wtf/WeakPtr.h"
@@ -43,7 +44,7 @@ class LayoutImageResource;
 template<typename T> class EventSender;
 using ImageEventSender = EventSender<ImageLoader>;
 
-class CORE_EXPORT ImageLoader : public NoBaseWillBeGarbageCollectedFinalized<ImageLoader>, public ImageResourceClient {
+class CORE_EXPORT ImageLoader : public NoBaseWillBeGarbageCollectedFinalized<ImageLoader>, public ResourceClient, public ImageResourceObserver {
     WILL_BE_USING_PRE_FINALIZER(ImageLoader, dispose);
     USING_FAST_MALLOC_WILL_BE_REMOVED(ImageLoader);
 public:
@@ -101,7 +102,7 @@ public:
     static void dispatchPendingLoadEvents();
     static void dispatchPendingErrorEvents();
 
-    bool getImageAnimationPolicy(ImageResource*, ImageAnimationPolicy&) final;
+    bool getImageAnimationPolicy(ImageAnimationPolicy&) final;
 protected:
     void notifyFinished(Resource*) override;
 
diff --git a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h b/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h
index fddaa2f..c9029c4 100644
--- a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h
+++ b/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h
@@ -8,7 +8,6 @@
 #include "core/fetch/CSSStyleSheetResource.h"
 #include "core/fetch/FontResource.h"
 #include "core/fetch/ImageResource.h"
-#include "core/fetch/ImageResourceClient.h"
 #include "core/fetch/RawResource.h"
 #include "core/fetch/ResourceLoader.h"
 #include "core/fetch/ResourceOwner.h"
@@ -110,7 +109,7 @@ private:
     }
 };
 
-class LinkPreloadImageResourceClient: public LinkPreloadResourceClient, public ResourceOwner<ImageResource, ImageResourceClient> {
+class LinkPreloadImageResourceClient: public LinkPreloadResourceClient, public ResourceOwner<ImageResource> {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(LinkPreloadImageResourceClient);
     USING_FAST_MALLOC_WILL_BE_REMOVED(LinkPreloadImageResourceClient);
 public:
@@ -133,7 +132,7 @@ public:
     DEFINE_INLINE_VIRTUAL_TRACE()
     {
         LinkPreloadResourceClient::trace(visitor);
-        ResourceOwner<ImageResource, ImageResourceClient>::trace(visitor);
+        ResourceOwner<ImageResource>::trace(visitor);
     }
 
 private:
diff --git a/third_party/WebKit/Source/core/style/StyleFetchedImage.cpp b/third_party/WebKit/Source/core/style/StyleFetchedImage.cpp
index 135b2b44..853b899 100644
--- a/third_party/WebKit/Source/core/style/StyleFetchedImage.cpp
+++ b/third_party/WebKit/Source/core/style/StyleFetchedImage.cpp
@@ -116,12 +116,12 @@ bool StyleFetchedImage::usesImageContainerSize() const
 
 void StyleFetchedImage::addClient(LayoutObject* layoutObject)
 {
-    m_image->addClient(layoutObject);
+    m_image->addObserver(layoutObject);
 }
 
 void StyleFetchedImage::removeClient(LayoutObject* layoutObject)
 {
-    m_image->removeClient(layoutObject);
+    m_image->removeObserver(layoutObject);
 }
 
 void StyleFetchedImage::notifyFinished(Resource* resource)
diff --git a/third_party/WebKit/Source/core/style/StyleFetchedImage.h b/third_party/WebKit/Source/core/style/StyleFetchedImage.h
index 4cf22ee..5bda657 100644
--- a/third_party/WebKit/Source/core/style/StyleFetchedImage.h
+++ b/third_party/WebKit/Source/core/style/StyleFetchedImage.h
@@ -24,7 +24,7 @@
 #ifndef StyleFetchedImage_h
 #define StyleFetchedImage_h
 
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ResourceClient.h"
 #include "core/style/StyleImage.h"
 
 namespace blink {
@@ -32,7 +32,7 @@ namespace blink {
 class Document;
 class ImageResource;
 
-class StyleFetchedImage final : public StyleImage, private ImageResourceClient {
+class StyleFetchedImage final : public StyleImage, private ResourceClient {
     USING_FAST_MALLOC_WILL_BE_REMOVED(StyleFetchedImage);
     WILL_BE_USING_PRE_FINALIZER(StyleFetchedImage, dispose);
 public:
diff --git a/third_party/WebKit/Source/core/style/StyleFetchedImageSet.cpp b/third_party/WebKit/Source/core/style/StyleFetchedImageSet.cpp
index 6c7b5e6..18158dd 100644
--- a/third_party/WebKit/Source/core/style/StyleFetchedImageSet.cpp
+++ b/third_party/WebKit/Source/core/style/StyleFetchedImageSet.cpp
@@ -120,12 +120,12 @@ bool StyleFetchedImageSet::usesImageContainerSize() const
 
 void StyleFetchedImageSet::addClient(LayoutObject* layoutObject)
 {
-    m_bestFitImage->addClient(layoutObject);
+    m_bestFitImage->addObserver(layoutObject);
 }
 
 void StyleFetchedImageSet::removeClient(LayoutObject* layoutObject)
 {
-    m_bestFitImage->removeClient(layoutObject);
+    m_bestFitImage->removeObserver(layoutObject);
 }
 
 PassRefPtr<Image> StyleFetchedImageSet::image(const LayoutObject&, const IntSize& containerSize, float zoom) const
diff --git a/third_party/WebKit/Source/core/style/StyleFetchedImageSet.h b/third_party/WebKit/Source/core/style/StyleFetchedImageSet.h
index 0d6ba2c..f45652e 100644
--- a/third_party/WebKit/Source/core/style/StyleFetchedImageSet.h
+++ b/third_party/WebKit/Source/core/style/StyleFetchedImageSet.h
@@ -26,7 +26,7 @@
 #ifndef StyleFetchedImageSet_h
 #define StyleFetchedImageSet_h
 
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ResourceClient.h"
 #include "core/style/StyleImage.h"
 #include "platform/geometry/LayoutSize.h"
 
@@ -37,7 +37,7 @@ class CSSImageSetValue;
 
 // This class keeps one cached image and has access to a set of alternatives.
 
-class StyleFetchedImageSet final : public StyleImage, private ImageResourceClient {
+class StyleFetchedImageSet final : public StyleImage, private ResourceClient {
     USING_FAST_MALLOC_WILL_BE_REMOVED(StyleFetchedImageSet);
     WILL_BE_USING_PRE_FINALIZER(StyleFetchedImageSet, dispose);
 public:
diff --git a/third_party/WebKit/Source/core/svg/SVGFEImageElement.h b/third_party/WebKit/Source/core/svg/SVGFEImageElement.h
index 4df7845..ae6b4f5 100644
--- a/third_party/WebKit/Source/core/svg/SVGFEImageElement.h
+++ b/third_party/WebKit/Source/core/svg/SVGFEImageElement.h
@@ -23,7 +23,7 @@
 
 #include "core/SVGNames.h"
 #include "core/fetch/ImageResource.h"
-#include "core/fetch/ImageResourceClient.h"
+#include "core/fetch/ResourceClient.h"
 #include "core/svg/SVGAnimatedPreserveAspectRatio.h"
 #include "core/svg/SVGFilterPrimitiveStandardAttributes.h"
 #include "core/svg/SVGURIReference.h"
@@ -33,7 +33,7 @@ namespace blink {
 
 class SVGFEImageElement final : public SVGFilterPrimitiveStandardAttributes,
                                 public SVGURIReference,
-                                public ImageResourceClient {
+                                public ResourceClient {
     DEFINE_WRAPPERTYPEINFO();
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(SVGFEImageElement);
 public: