[Slimming Paint] Add *FilterDisplayItem type for slimming paint

Source/core/paint/ViewDisplayList.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/paint/ViewDisplayList.h"
 
 #include "platform/NotImplemented.h"
 #include "platform/RuntimeEnabledFeatures.h"
 
@@ skipping 128 matching lines @@
     case DisplayItem::ClipLayerFragmentFloat: return "ClipLayerFragmentFloat";
     case DisplayItem::ClipLayerFragmentForeground: return "ClipLayerFragmentForeground";
     case DisplayItem::ClipLayerFragmentChildOutline: return "ClipLayerFragmentChildOutline";
     case DisplayItem::ClipLayerFragmentOutline: return "ClipLayerFragmentOutline";
     case DisplayItem::ClipLayerFragmentMask: return "ClipLayerFragmentMask";
     case DisplayItem::ClipLayerFragmentClippingMask: return "ClipLayerFragmentClippingMask";
     case DisplayItem::ClipLayerFragmentParent: return "ClipLayerFragmentParent";
     case DisplayItem::ClipLayerFragmentSelection: return "ClipLayerFragmentSelection";
     case DisplayItem::ClipLayerFragmentChildBlockBackgrounds: return "ClipLayerFragmentChildBlockBackgrounds";
     case DisplayItem::EndClip: return "EndClip";
+    case DisplayItem::BeginFilter: return "BeginFilter";
+    case DisplayItem::EndFilter: return "EndFilter";
     }
     ASSERT_NOT_REACHED();
     return "Unknown";
 }
 
 WTF::String DisplayItem::rendererDebugString(const RenderObject* renderer)
 {
     if (renderer && renderer->node())
         return String::format("nodeName: \"%s\", renderer: \"%p\"", renderer->node()->nodeName().utf8().data(), renderer);
     return String::format("renderer: \"%p\"", renderer);
@@ skipping 18 matching lines @@
 }
 
 void ViewDisplayList::showDebugData() const
 {
     fprintf(stderr, "paint list: [%s]\n", paintListAsDebugString(m_paintList).utf8().data());
     fprintf(stderr, "new paints: [%s]\n", paintListAsDebugString(m_newPaints).utf8().data());
 }
 #endif
 
 } // namespace blink