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

third_party/WebKit/Source/platform/graphics/paint/SubsequenceDisplayItem.h

Index: third_party/WebKit/Source/platform/graphics/paint/SubsequenceDisplayItem.h
diff --git a/third_party/WebKit/Source/platform/graphics/paint/SubsequenceDisplayItem.h b/third_party/WebKit/Source/platform/graphics/paint/SubsequenceDisplayItem.h
new file mode 100644
index 0000000000000000000000000000000000000000..611ca093808d1dbb4581c5b42d1677e5989982af
--- /dev/null
+++ b/third_party/WebKit/Source/platform/graphics/paint/SubsequenceDisplayItem.h
@@ -0,0 +1,34 @@
+// Copyright 2015 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.
+
+#ifndef SubsequenceDisplayItem_h
+#define SubsequenceDisplayItem_h
+
+#include "platform/geometry/FloatRect.h"
+#include "platform/graphics/paint/DisplayItem.h"
+#include "platform/wtf/Assertions.h"
+
+namespace blink {
+
+class BeginSubsequenceDisplayItem final : public PairedBeginDisplayItem {
+ public:
+  BeginSubsequenceDisplayItem(const DisplayItemClient& client)
+      : PairedBeginDisplayItem(client, kSubsequence, sizeof(*this)) {}
+};
+
+class EndSubsequenceDisplayItem final : public PairedEndDisplayItem {
+ public:
+  EndSubsequenceDisplayItem(const DisplayItemClient& client)
+      : PairedEndDisplayItem(client, kEndSubsequence, sizeof(*this)) {}
+
+#if DCHECK_IS_ON()
+  bool isEndAndPairedWith(DisplayItem::Type otherType) const final {
+    return getType() == kEndSubsequence && otherType == kSubsequence;
+  }
+#endif
+};
+
+}  // namespace blink
+
+#endif  // SubsequenceDisplayItem_h