[DMC #2] Add DocumentMarkerList interface and GenericDocumentMarkerListImpl

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

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarkerList.h
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarkerList.h b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerList.h
new file mode 100644
index 0000000000000000000000000000000000000000..f3f446f45185092b571a22565be3c75dce4f5d53
--- /dev/null
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerList.h
@@ -0,0 +1,44 @@
+// 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 DocumentMarkerList_h
+#define DocumentMarkerList_h
+
+#include "core/editing/markers/DocumentMarker.h"
+#include "platform/heap/Handle.h"
+
+namespace blink {
+
+class CORE_EXPORT DocumentMarkerList
+    : public GarbageCollectedFinalized<DocumentMarkerList> {
+ public:
+  DocumentMarkerList();
+
+  virtual ~DocumentMarkerList();
+
+  virtual bool IsEmpty() const = 0;
+
+  virtual void Add(DocumentMarker*) = 0;
+  virtual void Clear() = 0;
+
+  virtual void AppendMarkersToInputList(DocumentMarkerVector* list) const = 0;
+
+  // Returns true if at least one marker is copied, false otherwise
+  virtual bool MoveMarkers(int length, DocumentMarkerList* dst_list) = 0;
+
+  // Returns true if at least one marker is removed, false otherwise
+  virtual bool RemoveMarkers(unsigned start_offset, int length) = 0;
+
+  // Returns true if at least one marker is shifted or removed, false otherwise
+  virtual bool ShiftMarkers(unsigned offset,
+                            unsigned old_length,
+                            unsigned new_length) = 0;
+
+  DEFINE_INLINE_VIRTUAL_TRACE() {}
+  DISALLOW_COPY_AND_ASSIGN(DocumentMarkerList);
+};
+
+}  // namespace blink
+
+#endif  // DocumentMarkerList_h