[Interpreter] Preserve source positions in peephole optimizer.

test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden

Index: test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden
diff --git a/test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden b/test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden
index c80469b303f92849a88dcb46b5a7ba88b395a793..09e62f19be36bd0b398a2eec8b0a968c59a9ff9d 100644
--- a/test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden
+++ b/test/cctest/interpreter/bytecode_expectations/AssignmentsInBinaryExpression.golden
@@ -44,7 +44,7 @@ snippet: "
 "
 frame size: 2
 parameter count: 1
-bytecode array length: 12
+bytecode array length: 13
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(55),
@@ -52,6 +52,7 @@ bytecodes: [
   /*   57 S> */ B(LdaSmi), U8(100),
   /*   57 E> */ B(Star), R(0),
   /*   57 E> */ B(Star), R(1),
+  /*   65 S> */ B(Nop),
   /*   75 S> */ B(Return),
 ]
 constant pool: [
@@ -67,7 +68,7 @@ snippet: "
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 24
+bytecode array length: 25
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(55),
@@ -81,6 +82,7 @@ bytecodes: [
   /*   69 E> */ B(Star), R(0),
                 B(Add), R(2),
   /*   48 E> */ B(Star), R(0),
+  /*   77 S> */ B(Nop),
   /*   87 S> */ B(Return),
 ]
 constant pool: [
@@ -97,7 +99,7 @@ snippet: "
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 32
+bytecode array length: 33
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(55),
@@ -116,6 +118,7 @@ bytecodes: [
                 B(Star), R(1),
                 B(Inc),
   /*   76 E> */ B(Star), R(0),
+  /*   80 S> */ B(Nop),
   /*   90 S> */ B(Return),
 ]
 constant pool: [
@@ -131,7 +134,7 @@ snippet: "
 "
 frame size: 4
 parameter count: 1
-bytecode array length: 32
+bytecode array length: 33
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(55),
@@ -149,6 +152,7 @@ bytecodes: [
   /*   81 E> */ B(Star), R(0),
                 B(Add), R(2),
   /*   76 E> */ B(Star), R(1),
+  /*   87 S> */ B(Nop),
   /*   97 S> */ B(Return),
 ]
 constant pool: [
@@ -164,7 +168,7 @@ snippet: "
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 32
+bytecode array length: 33
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(55),
@@ -182,6 +186,7 @@ bytecodes: [
   /*   81 E> */ B(Star), R(0),
                 B(Add), R(1),
   /*   76 E> */ B(Star), R(0),
+  /*   87 S> */ B(Nop),
   /*   97 S> */ B(Return),
 ]
 constant pool: [