[interpreter, debugger] implement bytecode break location iterator.

src/interpreter/bytecode-array-builder.h

Index: src/interpreter/bytecode-array-builder.h
diff --git a/src/interpreter/bytecode-array-builder.h b/src/interpreter/bytecode-array-builder.h
index 7d1dbebe5de9d8b1835d684056e9eb7834851323..9bf7c6d115214eed28ee242b0b3aa8caf156e68b 100644
--- a/src/interpreter/bytecode-array-builder.h
+++ b/src/interpreter/bytecode-array-builder.h
@@ -256,6 +256,7 @@ class BytecodeArrayBuilder final : public ZoneObject, private RegisterMover {
   // entry, so that it can be referenced by above exception handling support.
   int NewHandlerEntry() { return handler_table_builder()->NewHandlerEntry(); }
 
+  void SetReturnPosition(FunctionLiteral* fun);
   void SetStatementPosition(Statement* stmt);
   void SetExpressionPosition(Expression* expr);
 
@@ -268,6 +269,8 @@ class BytecodeArrayBuilder final : public ZoneObject, private RegisterMover {
     return &temporary_allocator_;
   }
 
+  void EnsureReturn(FunctionLiteral* literal);
+
  private:
   class PreviousBytecodeHelper;
   friend class BytecodeRegisterAllocator;
@@ -324,7 +327,6 @@ class BytecodeArrayBuilder final : public ZoneObject, private RegisterMover {
       const ZoneVector<uint8_t>::iterator& jump_location, int delta);
 
   void LeaveBasicBlock();
-  void EnsureReturn();
 
   bool OperandIsValid(Bytecode bytecode, int operand_index,
                       uint32_t operand_value) const;