Raise the loading priority of in-viewport images.

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index a4b7d13e5d2836afeccba621e21ca5d50954815d..3dad271427e5ccd6fb455cc7d432a3eeca81434c 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -35,6 +35,7 @@
 #include "core/editing/EditingBoundary.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/htmlediting.h"
+#include "core/fetch/ResourceLoader.h"
 #include "core/html/HTMLAnchorElement.h"
 #include "core/html/HTMLElement.h"
 #include "core/html/HTMLHtmlElement.h"
@@ -2839,6 +2840,24 @@ void RenderObject::layout()
     clearNeedsLayout();
 }
 
+void RenderObject::didLayout(ResourceLoadPriorityOptimizer& priorityModifier)
+{
+    RenderObject* child = firstChild();
+    while (child) {
+        child->didLayout(priorityModifier);
+        child = child->nextSibling();
+    }
+}
+
+void RenderObject::didScroll(ResourceLoadPriorityOptimizer& priorityModifier)
+{
+    RenderObject* child = firstChild();
+    while (child) {
+        child->didScroll(priorityModifier);
+        child = child->nextSibling();
+    }
+}
+
 void RenderObject::forceLayout()
 {
     setSelfNeedsLayout(true);