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

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

Index: third_party/WebKit/Source/core/editing/markers/CompositionMarker.cpp
diff --git a/third_party/WebKit/Source/core/editing/markers/CompositionMarker.cpp b/third_party/WebKit/Source/core/editing/markers/CompositionMarker.cpp
index f445f502b496b4608790cf16e0b725f2a00e337a..f24217de7f541dce3e5b7f93a3ee73c419df9682 100644
--- a/third_party/WebKit/Source/core/editing/markers/CompositionMarker.cpp
+++ b/third_party/WebKit/Source/core/editing/markers/CompositionMarker.cpp
@@ -11,11 +11,15 @@ CompositionMarker::CompositionMarker(unsigned start_offset,
                                      Color underline_color,
                                      bool thick,
                                      Color background_color)
-    : DocumentMarker(DocumentMarker::kComposition, start_offset, end_offset),
+    : DocumentMarker(start_offset, end_offset),
       underline_color_(underline_color),
       background_color_(background_color),
       thick_(thick) {}
 
+DocumentMarker::MarkerType CompositionMarker::GetType() const {
+  return DocumentMarker::kComposition;
+}
+
 Color CompositionMarker::UnderlineColor() const {
   return underline_color_;
 }