Fix position of floating layer whose containing block is also floating

third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp

Index: third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp b/third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp
index ebe6007f2e3d1407cfdf6c5b929741991dc77915..66172b83c5ce8126e3a17fc1d5428ed415440105 100644
--- a/third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/GraphicsLayerUpdater.cpp
@@ -57,6 +57,10 @@ class GraphicsLayerUpdater::UpdateContext {
     if (layer.stackingNode()->isStacked())
       return m_compositingStackingContext;
 
+    // TODO(wangxianzhu, chrishtr): This is incorrect if m_compositingAncestor
+    // is inline and there is any non-layer floating object between layer and
+    // m_compositingAncestor. Should use the logic in PaintLayer::
+    // containingLayer().
     if (layer.layoutObject().isFloatingWithNonContainingBlockParent())
       return layer.enclosingLayerWithCompositedLayerMapping(ExcludeSelf);