[test] Clean up a couple TODOs.

src/compiler/instruction.h

Index: src/compiler/instruction.h
diff --git a/src/compiler/instruction.h b/src/compiler/instruction.h
index e719bf53aa2e1622ea2cf1f1ead16023503c07a6..4d48101cc4e955281bb5c1dd53920105c7e35227 100644
--- a/src/compiler/instruction.h
+++ b/src/compiler/instruction.h
@@ -738,7 +738,6 @@ class Instruction final {
     return FlagsConditionField::decode(opcode());
   }
 
-  // TODO(titzer): make call into a flags.
   static Instruction* New(Zone* zone, InstructionCode opcode) {
     return New(zone, opcode, 0, nullptr, 0, nullptr, 0, nullptr);
   }