Fix -Wsign-compare errors in TF tests under GCC 4.9.2

test/unittests/compiler/node-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/compiler/node.h"
 #include "src/compiler/operator.h"
 #include "test/unittests/test-utils.h"
 #include "testing/gmock-support.h"
 
 using testing::ElementsAre;
@@ skipping 14 matching lines @@
 
 const Operator kOp0(kOpcode0, Operator::kNoProperties, "Op0", 0, 0, 0, 1, 0, 0);
 const Operator kOp1(kOpcode1, Operator::kNoProperties, "Op1", 1, 0, 0, 1, 0, 0);
 const Operator kOp2(kOpcode2, Operator::kNoProperties, "Op2", 2, 0, 0, 1, 0, 0);
 
 }  // namespace
 
 
 TEST_F(NodeTest, New) {
   Node* const node = Node::New(zone(), 1, &kOp0, 0, nullptr, false);
-  EXPECT_EQ(1, node->id());
+  EXPECT_EQ(1U, node->id());
   EXPECT_EQ(0, node->UseCount());
   EXPECT_TRUE(node->uses().empty());
   EXPECT_EQ(0, node->InputCount());
   EXPECT_TRUE(node->inputs().empty());
   EXPECT_EQ(&kOp0, node->op());
   EXPECT_EQ(kOpcode0, node->opcode());
 }
 
 
 TEST_F(NodeTest, NewWithInputs) {
@@ skipping 206 matching lines @@
     for (int i = 0; i < size; i++) {
       EXPECT_EQ(inputs[i], node->InputAt(i));
     }
   }
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8