[Interpreter] Preserve source positions in peephole optimizer.

test/cctest/interpreter/bytecode_expectations/ForIn.golden

Index: test/cctest/interpreter/bytecode_expectations/ForIn.golden
diff --git a/test/cctest/interpreter/bytecode_expectations/ForIn.golden b/test/cctest/interpreter/bytecode_expectations/ForIn.golden
index 2b61b6423b0d31cdaabb74f2f09b164430f09252..784198666a24df5be1b20aa8b4f59f90656ec743 100644
--- a/test/cctest/interpreter/bytecode_expectations/ForIn.golden
+++ b/test/cctest/interpreter/bytecode_expectations/ForIn.golden
@@ -65,30 +65,31 @@ snippet: "
 "
 frame size: 8
 parameter count: 1
-bytecode array length: 45
+bytecode array length: 46
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaConstant), U8(0),
   /*   42 E> */ B(Star), R(1),
-  /*   68 S> */ B(JumpIfUndefined), U8(38),
-                B(JumpIfNull), U8(36),
+  /*   68 S> */ B(JumpIfUndefined), U8(39),
+                B(JumpIfNull), U8(37),
                 B(ToObject),
                 B(Star), R(3),
                 B(ForInPrepare), R(4),
                 B(LdaZero),
                 B(Star), R(7),
   /*   63 S> */ B(ForInDone), R(7), R(6),
-                B(JumpIfTrue), U8(23),
+                B(JumpIfTrue), U8(24),
                 B(ForInNext), R(3), R(7), R(4), U8(1),
-                B(JumpIfUndefined), U8(10),
+                B(JumpIfUndefined), U8(11),
                 B(Star), R(0),
   /*   54 E> */ B(StackCheck),
                 B(Ldar), R(0),
                 B(Star), R(2),
+  /*   73 S> */ B(Nop),
   /*   85 S> */ B(Return),
                 B(ForInStep), R(7),
                 B(Star), R(7),
-                B(Jump), U8(-24),
+                B(Jump), U8(-25),
                 B(LdaUndefined),
   /*   85 S> */ B(Return),
 ]