Refactor ResourceLoadPriorityOptimizer to avoid walking render tree

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 77b99b30e0ff38e48b956bd8632a847308beca28..0cae614c97478e7c180872d2ef672cf99c6f15fc 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/ResourceLoadPriorityOptimizer.h"
 #include "core/fetch/ResourceLoader.h"
 #include "core/html/HTMLAnchorElement.h"
 #include "core/html/HTMLElement.h"
@@ -235,6 +236,7 @@ RenderObject::RenderObject(Node* node)
 
 RenderObject::~RenderObject()
 {
+    ResourceLoadPriorityOptimizer::resourceLoadPriorityOptimizer()->removeRenderObject(this);

[ojan, 2014/01/23 06:32:59]

Since we only ever add RenderImages, could we just call this from the
RenderImage destructor?

 #ifndef NDEBUG
     ASSERT(!m_hasAXObject);
     renderObjectCounter.decrement();
@@ -2860,18 +2862,6 @@ void RenderObject::scheduleRelayout()
     }
 }
 
-void RenderObject::didLayout(ResourceLoadPriorityOptimizer& priorityModifier)
-{
-    for (RenderObject* child = firstChild(); child; child = child->nextSibling())
-        child->didLayout(priorityModifier);
-}
-
-void RenderObject::didScroll(ResourceLoadPriorityOptimizer& priorityModifier)
-{
-    for (RenderObject* child = firstChild(); child; child = child->nextSibling())
-        child->didScroll(priorityModifier);
-}
-
 void RenderObject::forceLayout()
 {
     setSelfNeedsLayout(true);