Fix the bug that negative outline-offset is covered up by composited

third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 703 matching lines @@
     if (m_paintingPhase & GraphicsLayerPaintForeground)
       paintingPhasesJSON->pushString("GraphicsLayerPaintForeground");
     if (m_paintingPhase & GraphicsLayerPaintMask)
       paintingPhasesJSON->pushString("GraphicsLayerPaintMask");
     if (m_paintingPhase & GraphicsLayerPaintChildClippingMask)
       paintingPhasesJSON->pushString("GraphicsLayerPaintChildClippingMask");
     if (m_paintingPhase & GraphicsLayerPaintOverflowContents)
       paintingPhasesJSON->pushString("GraphicsLayerPaintOverflowContents");
     if (m_paintingPhase & GraphicsLayerPaintCompositedScroll)
       paintingPhasesJSON->pushString("GraphicsLayerPaintCompositedScroll");
+    if (m_paintingPhase & GraphicsLayerPaintDecoration)
+      paintingPhasesJSON->pushString("GraphicsLayerPaintDecoration");
     json->setArray("paintingPhases", std::move(paintingPhasesJSON));
   }
 
   if (flags & LayerTreeIncludesClipAndScrollParents) {
     if (m_hasScrollParent)
       json->setBoolean("hasScrollParent", true);
     if (m_hasClipParent)
       json->setBoolean("hasClipParent", true);
   }
 
@@ skipping 566 matching lines @@
 void showGraphicsLayerTree(const blink::GraphicsLayer* layer) {
   if (!layer) {
     fprintf(stderr, "Cannot showGraphicsLayerTree for (nil).\n");
     return;
   }
 
   String output = layer->layerTreeAsText(blink::LayerTreeIncludesDebugInfo);
   fprintf(stderr, "%s\n", output.utf8().data());
 }
 #endif