[DMC #5.55] Add DocumentMarkerList::MarkerType()

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

 // 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/CoreExport.h"
+#include "core/editing/markers/DocumentMarker.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
-class DocumentMarker;
 class RenderedDocumentMarker;
 
 // This is an interface implemented by classes that DocumentMarkerController
 // uses to store DocumentMarkers. Different implementations can be written
 // to handle different MarkerTypes (e.g. to provide more optimized handling of
 // MarkerTypes with different insertion/retrieval patterns, or to provide
 // different behavior for certain MarkerTypes).
 class CORE_EXPORT DocumentMarkerList
     : public GarbageCollectedFinalized<DocumentMarkerList> {
  public:
   virtual ~DocumentMarkerList();
 
+  // Returns the single marker type supported by the list implementation.
+  virtual DocumentMarker::MarkerType MarkerType() const = 0;
+
   virtual bool IsEmpty() const = 0;
 
   virtual void Add(DocumentMarker*) = 0;
   virtual void Clear() = 0;
 
   virtual const HeapVector<Member<RenderedDocumentMarker>>& GetMarkers()
       const = 0;
 
   // Returns true if at least one marker is copied, false otherwise
   virtual bool MoveMarkers(int length, DocumentMarkerList* dst_list) = 0;
@@ skipping 17 matching lines @@
  protected:
   DocumentMarkerList();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DocumentMarkerList);
 };
 
 }  // namespace blink
 
 #endif  // DocumentMarkerList_h