Refactor DocumentMarkerController

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

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarker.h
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.h b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.h
index 7db49d1a45320fa4724c6a664cb6a6d88e08a618..49c9508b0e8e2d60c5755b078091220122c99447 100644
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.h
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.h
@@ -118,8 +118,19 @@ class CORE_EXPORT DocumentMarker : public GarbageCollected<DocumentMarker> {
   void setActiveMatch(bool);
   void clearDetails() { m_details.clear(); }
 
-  // Offset modifications are done by DocumentMarkerController.
-  // Other classes should not call following setters.
+  struct ShiftMarkerResult {
+    unsigned newStartOffset;
+    unsigned newEndOffset;
+    bool shouldRemoveMarker;
+  };
+
+  ShiftMarkerResult getShiftedMarkerPosition(unsigned offset,
+                                             unsigned oldLength,
+                                             unsigned newLength) const;
+
+  // Offset modifications are done by DocumentMarkerController and the classes
+  // that implement the marker lists. Other classes should not call following
+  // setters.
   void setStartOffset(unsigned offset) { m_startOffset = offset; }
   void setEndOffset(unsigned offset) { m_endOffset = offset; }
   void shiftOffsets(int delta);