Document lifecycle violation

third_party/WebKit/Source/core/paint/PaintLayer.cpp

Index: third_party/WebKit/Source/core/paint/PaintLayer.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayer.cpp b/third_party/WebKit/Source/core/paint/PaintLayer.cpp
index f1f683b47c1d4b69f10391d4f6de1780a9c81348..9cc7012f2aa6217d91b7d44529fcac6b93b04bcf 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayer.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayer.cpp
@@ -2712,9 +2712,13 @@ void PaintLayer::filterNeedsPaintInvalidation()
     {
         DeprecatedScheduleStyleRecalcDuringLayout marker(layoutObject()->document().lifecycle());
         // It's possible for scheduleSVGFilterLayerUpdateHack to schedule a style recalc, which
-        // is a problem because this function can be called while performing layout.
-        // Presumably this represents an illegal data flow of layout or compositing
-        // information into the style system.
+        // is a problem because this function can be called right before performing layout but
+        // after style recalc.
+        //
+        // See LayoutView::layout() and the call to
+        // invalidateSVGRootsWithRelativeLengthDescendents(). This violation is worked around
+        // in FrameView::updateStyleAndLayoutIfNeededRecursive() by doing an extra style recalc
+        // and layout in case it's needed.
         toElement(layoutObject()->node())->scheduleSVGFilterLayerUpdateHack();
     }