[turbofan] Use appropriate type for NodeId.

src/compiler/loop-analysis.h

 // Copyright 2014 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.
 
 #ifndef V8_COMPILER_LOOP_ANALYSIS_H_
 #define V8_COMPILER_LOOP_ANALYSIS_H_
 
 #include "src/base/iterator.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/node.h"
@@ skipping 45 matching lines @@
     Loop* parent_;
     int depth_;
     ZoneVector<Loop*> children_;
     int header_start_;
     int body_start_;
     int body_end_;
   };
 
   // Return the innermost nested loop, if any, that contains {node}.
   Loop* ContainingLoop(Node* node) {
-    if (node->id() >= static_cast<int>(node_to_loop_num_.size()))
-      return nullptr;
+    if (node->id() >= node_to_loop_num_.size()) return nullptr;
     int num = node_to_loop_num_[node->id()];
     return num > 0 ? &all_loops_[num - 1] : nullptr;
   }
 
   // Check if the {loop} contains the {node}, either directly or by containing
   // a nested loop that contains {node}.
   bool Contains(Loop* loop, Node* node) {
     for (Loop* c = ContainingLoop(node); c != nullptr; c = c->parent_) {
       if (c == loop) return true;
     }
@@ skipping 70 matching lines @@
   // Build a loop tree for the entire graph.
   static LoopTree* BuildLoopTree(Graph* graph, Zone* temp_zone);
 };
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_LOOP_ANALYSIS_H_