[ignition] Fix -Wsign-compare warnings.

src/interpreter/bytecode-register-optimizer.h

Index: src/interpreter/bytecode-register-optimizer.h
diff --git a/src/interpreter/bytecode-register-optimizer.h b/src/interpreter/bytecode-register-optimizer.h
index 885f10f3441e9159c5a6a24063d0de5480adfdcb..c8139484b4d5721bebefa888ba0aa89426ca8158 100644
--- a/src/interpreter/bytecode-register-optimizer.h
+++ b/src/interpreter/bytecode-register-optimizer.h
@@ -137,7 +137,7 @@ class V8_EXPORT_PRIVATE BytecodeRegisterOptimizer final
 
   uint32_t NextEquivalenceId() {
     equivalence_id_++;
-    CHECK_NE(equivalence_id_, kInvalidEquivalenceId);
+    CHECK_NE(static_cast<size_t>(equivalence_id_), kInvalidEquivalenceId);

[rmcilroy, 2016/11/10 08:54:43]

Could you add a TODO for me to make these the same type.

[ulan, 2016/11/10 10:59:22]

Done.

     return equivalence_id_;
   }