DocumentMarkerList refactor as an interface

third_party/WebKit/Source/core/editing/markers/CompositionMarkerList.h

Index: third_party/WebKit/Source/core/editing/markers/CompositionMarkerList.h
diff --git a/third_party/WebKit/Source/core/editing/markers/CompositionMarkerList.h b/third_party/WebKit/Source/core/editing/markers/CompositionMarkerList.h
new file mode 100644
index 0000000000000000000000000000000000000000..575798e9b3dfd82d01cc229b64e3ef228e83c45f
--- /dev/null
+++ b/third_party/WebKit/Source/core/editing/markers/CompositionMarkerList.h
@@ -0,0 +1,56 @@
+// Copyright 2017 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 CompositionMarkerList_h
+#define CompositionMarkerList_h
+
+#include "core/editing/markers/DocumentMarkerList.h"
+
+namespace blink {
+
+class CORE_EXPORT CompositionMarkerList final : public DocumentMarkerList {
+ public:
+  CompositionMarkerList();
+
+  DocumentMarker::MarkerType allowedMarkerType() const final;
+
+  bool empty() const final;
+  DocumentMarker* at(size_t index) final;
+
+  void add(DocumentMarker*) final;
+  void clear() final;
+
+  void appendMarkersToInputList(DocumentMarkerVector* list) const;
+
+  DidCopyMarkerOrNot copyMarkers(unsigned startOffset,
+                                 int length,
+                                 DocumentMarkerList* dstList,
+                                 int delta) final;
+
+  DidRemoveMarkerOrNot removeMarkers(
+      unsigned startOffset,
+      int length,
+      bool shouldRemovePartiallyOverlappingMarkers) final;
+
+  DidShiftMarkerOrNot shiftMarkers(unsigned offset,
+                                   unsigned oldLength,
+                                   unsigned newLength) final;
+
+  DECLARE_VIRTUAL_TRACE();
+
+ private:
+  HeapVector<Member<DocumentMarker>> m_markers;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositionMarkerList);
+};
+
+DEFINE_TYPE_CASTS(CompositionMarkerList,
+                  DocumentMarkerList,
+                  list,
+                  list->allowedMarkerType() == DocumentMarker::Composition,
+                  list.allowedMarkerType() == DocumentMarker::Composition);
+
+}  // namespace blink
+
+#endif  // CompositionMarkerList_h