Revert of Remove begin/end subseq. display items, and store on PaintController instead.

third_party/WebKit/Source/platform/graphics/paint/DisplayItem.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 "platform/graphics/paint/DisplayItem.h"
 
 namespace blink {
 
 struct SameSizeAsDisplayItem {
   virtual ~SameSizeAsDisplayItem() {}  // Allocate vtable pointer.
@@ skipping 199 matching lines @@
 
   switch (type) {
     DEBUG_STRING_CASE(BeginFilter);
     DEBUG_STRING_CASE(EndFilter);
     DEBUG_STRING_CASE(BeginCompositing);
     DEBUG_STRING_CASE(EndCompositing);
     DEBUG_STRING_CASE(BeginTransform);
     DEBUG_STRING_CASE(EndTransform);
     DEBUG_STRING_CASE(BeginClipPath);
     DEBUG_STRING_CASE(EndClipPath);
+    DEBUG_STRING_CASE(Subsequence);
+    DEBUG_STRING_CASE(EndSubsequence);
     DEBUG_STRING_CASE(UninitializedType);
     DEFAULT_CASE;
   }
 }
 
 WTF::String DisplayItem::asDebugString() const {
   WTF::StringBuilder stringBuilder;
   stringBuilder.append('{');
   dumpPropertiesAsDebugString(stringBuilder);
   stringBuilder.append('}');
@@ skipping 17 matching lines @@
   stringBuilder.append("\", type: \"");
   stringBuilder.append(typeAsDebugString(getType()));
   stringBuilder.append('"');
   if (m_skippedCache)
     stringBuilder.append(", skippedCache: true");
 }
 
 #endif
 
 }  // namespace blink