[interpreter] Minor clean-up of BytecodeSourceInfo.

test/unittests/interpreter/bytecode-register-optimizer-unittest.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/factory.h"
 #include "src/interpreter/bytecode-label.h"
 #include "src/interpreter/bytecode-register-optimizer.h"
 #include "src/objects-inl.h"
@@ skipping 57 matching lines @@
   Initialize(1, 1);
   BytecodeNode node(Bytecode::kNop);
   optimizer()->Write(&node);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(node, last_written());
 }
 
 TEST_F(BytecodeRegisterOptimizerTest, WriteNopExpression) {
   Initialize(1, 1);
   BytecodeNode node(Bytecode::kNop);
-  node.source_info().Update({3, false});
+  node.source_info().MakeExpressionPosition(3);
   optimizer()->Write(&node);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(node, last_written());
 }
 
 TEST_F(BytecodeRegisterOptimizerTest, WriteNopStatement) {
   Initialize(1, 1);
   BytecodeNode node(Bytecode::kNop);
-  node.source_info().Update({3, true});
+  node.source_info().MakeStatementPosition(3);
   optimizer()->Write(&node);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(node, last_written());
 }
 
 TEST_F(BytecodeRegisterOptimizerTest, TemporaryMaterializedForJump) {
   Initialize(1, 1);
   Register temp = NewTemporary();
   BytecodeNode node(Bytecode::kStar, temp.ToOperand());
   optimizer()->Write(&node);
@@ skipping 112 matching lines @@
 
   CHECK_EQ(output()->at(3).bytecode(), Bytecode::kCallJSRuntime);
   CHECK_EQ(output()->at(3).operand(0), 0);
   CHECK_EQ(output()->at(3).operand(1), temp0.ToOperand());
   CHECK_EQ(output()->at(3).operand(2), 2);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8