Move RenderLayer repainting to repaint-after-layout framework.

Source/core/rendering/RenderBlock.cpp

Index: Source/core/rendering/RenderBlock.cpp
diff --git a/Source/core/rendering/RenderBlock.cpp b/Source/core/rendering/RenderBlock.cpp
index 410ccea586f7631dfdd2cba1cb7633a9dbb0d37d..824f31fee40044fe0a14ab1e92af1f91d2e188e4 100644
--- a/Source/core/rendering/RenderBlock.cpp
+++ b/Source/core/rendering/RenderBlock.cpp
@@ -1745,6 +1745,8 @@ void RenderBlock::layoutPositionedObjects(bool relayoutChildren, bool fixedPosit
     for (TrackedRendererListHashSet::iterator it = positionedDescendants->begin(); it != end; ++it) {
         r = *it;
 
+        LayoutRectRecorder recorder(*r);
+
         SubtreeLayoutScope layoutScope(r);
         // A fixed position element with an absolute positioned ancestor has no way of knowing if the latter has changed position. So
         // if this is a fixed position element, mark it for layout if it has an abspos ancestor and needs to move with that ancestor, i.e.
@@ -1786,7 +1788,10 @@ void RenderBlock::layoutPositionedObjects(bool relayoutChildren, bool fixedPosit
             oldLogicalTop = logicalTopForChild(r);
         }
 
-        r->layoutIfNeeded();
+        if (r->needsLayout())
+            r->layout();
+        else
+            r->setShouldDoFullRepaintAfterLayout(true);

[Julien - ping for review, 2014/03/04 18:22:10]

This will cause all positioned objects to be repainted, even when they didn't
need layout.

[dsinclair, 2014/03/04 19:21:52]

Done.

 
         // Lay out again if our estimate was wrong.
         if (needsBlockDirectionLocationSetBeforeLayout && logicalTopForChild(r) != oldLogicalTop)