Add Smi::Zero and replace all Smi::FromInt(0) calls

test/unittests/interpreter/bytecode-array-iterator-unittest.cc

 // Copyright 2015 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/interpreter/bytecode-array-builder.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "test/unittests/test-utils.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 class BytecodeArrayIteratorTest : public TestWithIsolateAndZone {
  public:
   BytecodeArrayIteratorTest() {}
   ~BytecodeArrayIteratorTest() override {}
 };
 
 
 TEST_F(BytecodeArrayIteratorTest, IteratesBytecodeArray) {
   // Use a builder to create an array with containing multiple bytecodes
   // with 0, 1 and 2 operands.
   BytecodeArrayBuilder builder(isolate(), zone(), 3, 3, 0);
   Factory* factory = isolate()->factory();
   Handle<HeapObject> heap_num_0 = factory->NewHeapNumber(2.718);
   Handle<HeapObject> heap_num_1 = factory->NewHeapNumber(2147483647);
-  Smi* zero = Smi::FromInt(0);
+  Smi* zero = Smi::kZero;
   Smi* smi_0 = Smi::FromInt(64);
   Smi* smi_1 = Smi::FromInt(-65536);
   Register reg_0(0);
   Register reg_1(1);
   RegisterList pair(0, 2);
   RegisterList triple(0, 3);
   Register param = Register::FromParameterIndex(2, builder.parameter_count());
   Handle<String> name = factory->NewStringFromStaticChars("abc");
   int name_index = 2;
   int feedback_slot = 97;
@@ skipping 238 matching lines @@
   CHECK_EQ(iterator.current_offset(), offset);
   CHECK_EQ(iterator.current_operand_scale(), OperandScale::kSingle);
   CHECK(!iterator.done());
   iterator.Advance();
   CHECK(iterator.done());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8