Use source position table for unoptimized code.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index eb464399b8e78ac21d11eaa7cee6146da5942dd9..dc9d7071d728cd5644346b6a24937f4f508b11ac 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -4923,6 +4923,9 @@ class Code: public HeapObject {
   // [deoptimization_data]: Array containing data for deopt.
   DECL_ACCESSORS(deoptimization_data, FixedArray)
 
+  // [source_position_table]: ByteArray for the source positions table.
+  DECL_ACCESSORS(source_position_table, ByteArray)
+
   // [raw_type_feedback_info]: This field stores various things, depending on
   // the kind of the code object.
   //   FUNCTION           => type feedback information.
@@ -5244,9 +5247,11 @@ class Code: public HeapObject {
   static const int kHandlerTableOffset = kRelocationInfoOffset + kPointerSize;
   static const int kDeoptimizationDataOffset =
       kHandlerTableOffset + kPointerSize;
+  static const int kSourcePositionTableOffset =
+      kDeoptimizationDataOffset + kPointerSize;
   // For FUNCTION kind, we store the type feedback info here.
   static const int kTypeFeedbackInfoOffset =
-      kDeoptimizationDataOffset + kPointerSize;
+      kSourcePositionTableOffset + kPointerSize;
   static const int kNextCodeLinkOffset = kTypeFeedbackInfoOffset + kPointerSize;
   static const int kGCMetadataOffset = kNextCodeLinkOffset + kPointerSize;
   static const int kInstructionSizeOffset = kGCMetadataOffset + kPointerSize;