[DMC #25] Make DocumentMarker::GetType() virtual

third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
index 1d74d9f2ee4caff9e36dfd8fe3aaa976fd170d72..4fc895502613fbcb084dc76629219656699de0aa 100644
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
@@ -36,10 +36,8 @@ namespace blink {
 
 DocumentMarker::~DocumentMarker() {}
 
-DocumentMarker::DocumentMarker(MarkerType type,
-                               unsigned start_offset,
-                               unsigned end_offset)
-    : type_(type), start_offset_(start_offset), end_offset_(end_offset) {}
+DocumentMarker::DocumentMarker(unsigned start_offset, unsigned end_offset)
+    : start_offset_(start_offset), end_offset_(end_offset) {}
 
 Optional<DocumentMarker::MarkerOffsets>
 DocumentMarker::ComputeOffsetsAfterShift(unsigned offset,