[DMC #5] Add SpellCheckMarkerListImpl

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 "platform/heap/Handle.h"
 
@@ skipping 19 matching lines @@
 
   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;
 
   // Returns true if at least one marker is removed, false otherwise
   virtual bool RemoveMarkers(unsigned start_offset, int length) = 0;
 
-  // Returns true if a marker was removed, false otherwise.
-  // TODO(rlanday): remove this method from this interface once we have a
-  // Spelling/Grammar-specific marker list impl to put this on
-  virtual bool RemoveMarkersUnderWords(const String& node_text,

[yosin_UTC9, 2017/05/08 04:50:54]

Could you make this patch into two patches?
1. Introduce SpellinMarkerListImpl
2. Move AddMarkerAndMergeOverlapping()
3. Introduce type case (DEFINE_TYPE_CASTS) for DocumentMarkerList
4. Move RemoveMarkersUnderWords()

-                                       const Vector<String>& words) = 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() {}
 
  protected:
   DocumentMarkerList();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DocumentMarkerList);
 };
 
 }  // namespace blink
 
 #endif  // DocumentMarkerList_h