Emit source positions in deopt comments, too.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index ab571470a934c1992eb9659d82e5a2feb77db9cc..695c629a7049dc051fdc33a06751ef7ecadce622 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -455,10 +455,10 @@ class HSourcePosition {
   // Offset from the start of the inlined function.
   typedef BitField<int, 9, 23> PositionField;
 
-  // On HPositionInfo can use this constructor.
   explicit HSourcePosition(int value) : value_(value) { }
 
   friend class HPositionInfo;
+  friend class LCodeGenBase;
 
   // If FLAG_hydrogen_track_positions is set contains bitfields InliningIdField
   // and PositionField.