Replace collectLayerFragments() with FragmentainerIterator.

third_party/WebKit/Source/core/layout/LayoutFlowThread.h

Index: third_party/WebKit/Source/core/layout/LayoutFlowThread.h
diff --git a/third_party/WebKit/Source/core/layout/LayoutFlowThread.h b/third_party/WebKit/Source/core/layout/LayoutFlowThread.h
index 9700f126718995b41b0bd704f857c01059e5e4f9..d4f056f6c345804786b659b0f376b39476d1aabb 100644
--- a/third_party/WebKit/Source/core/layout/LayoutFlowThread.h
+++ b/third_party/WebKit/Source/core/layout/LayoutFlowThread.h
@@ -32,7 +32,6 @@
 
 #include "core/CoreExport.h"
 #include "core/layout/LayoutBlockFlow.h"
-#include "core/paint/PaintLayerFragment.h"
 #include "wtf/ListHashSet.h"
 
 namespace blink {
@@ -117,8 +116,6 @@ public:
     virtual bool isPageLogicalHeightKnown() const { return true; }
     bool pageLogicalSizeChanged() const { return m_pageLogicalSizeChanged; }
 
-    void collectLayerFragments(PaintLayerFragments&, const LayoutRect& layerBoundingBox, const LayoutRect& dirtyRectInMulticolContainer);
-
     // Return the visual bounding box based on the supplied flow-thread bounding box. Both
     // rectangles are completely physical in terms of writing mode.
     LayoutRect fragmentsBoundingBox(const LayoutRect& layerBoundingBox) const;