DO NOT SUBMIT really old prototype of sprite recognition for image replacement

third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp

Index: third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp
diff --git a/third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp b/third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp
index 78c5335250e14d1948f73e9cb5d2662d7dbad87a..b71e3bcb0e15621898eeeac00dc0ea30472074c6 100644
--- a/third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp
+++ b/third_party/WebKit/Source/core/css/resolver/ElementStyleResources.cpp
@@ -28,7 +28,9 @@
 #include "core/css/CSSImageValue.h"
 #include "core/css/CSSURIValue.h"
 #include "core/dom/Document.h"
+#include "core/fetch/ImageResource.h"
 #include "core/fetch/ResourceFetcher.h"
+#include "core/frame/Settings.h"
 #include "core/layout/svg/ReferenceFilterBuilder.h"
 #include "core/style/ComputedStyle.h"
 #include "core/style/ContentData.h"
@@ -41,6 +43,8 @@
 #include "core/style/StyleImage.h"
 #include "core/style/StyleInvalidImage.h"
 #include "core/style/StylePendingImage.h"
+#include "platform/Length.h"
+#include "platform/LengthPoint.h"
 
 namespace blink {
 
@@ -133,10 +137,27 @@ void ElementStyleResources::loadPendingSVGDocuments(ComputedStyle* computedStyle
     }
 }
 
+static bool isSprite(const ComputedStyle& style)
+{
+    if (!style.hasBackgroundImage())
+        return false;
+
+    const FillLayer& background = style.backgroundLayers();
+    return (background.xPosition().isFixed() && !background.xPosition().isZero())
+        || (background.yPosition().isFixed() && !background.yPosition().isZero());
+}
+
+static ImageResource::PlaceholderRequestType determinePlaceholderRequestType(const Document& document, const ComputedStyle& style)
+{
+    return document.settings() && document.settings()->fetchImagePlaceholders() && !isSprite(style)
+        ? ImageResource::PlaceholderRequestType::AllowPlaceholder
+        : ImageResource::PlaceholderRequestType::DisallowPlaceholder;
+}
+
 StyleImage* ElementStyleResources::loadPendingImage(ComputedStyle* style, StylePendingImage* pendingImage, CrossOriginAttributeValue crossOrigin)
 {
     if (CSSImageValue* imageValue = pendingImage->cssImageValue())
-        return imageValue->cacheImage(*m_document, crossOrigin);
+        return imageValue->cacheImage(*m_document, crossOrigin, determinePlaceholderRequestType(*m_document, *style));
 
     if (CSSPaintValue* paintValue = pendingImage->cssPaintValue()) {
         StyleGeneratedImage* image = StyleGeneratedImage::create(*paintValue);
@@ -153,7 +174,7 @@ StyleImage* ElementStyleResources::loadPendingImage(ComputedStyle* style, StyleP
         return cursorImageValue->cacheImage(*m_document, m_deviceScaleFactor);
 
     if (CSSImageSetValue* imageSetValue = pendingImage->cssImageSetValue())
-        return imageSetValue->cacheImage(*m_document, m_deviceScaleFactor, crossOrigin);
+        return imageSetValue->cacheImage(*m_document, m_deviceScaleFactor, crossOrigin, determinePlaceholderRequestType(*m_document, *style));
 
     ASSERT_NOT_REACHED();
     return nullptr;