DBC: Enable CpuInfo test

runtime/vm/cpu_dbc.h

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_CPU_DBC_H_
 #define VM_CPU_DBC_H_
 
 #include "vm/allocation.h"
 #include "vm/simulator.h"
 
 namespace dart {
 
 class HostCPUFeatures: public AllStatic {
  public:
-  static const char* hardware() { return "simdbc"; }
+  static void InitOnce();
+  static void Cleanup();
+
+  static const char* hardware() {
+    DEBUG_ASSERT(initialized_);
+    return hardware_;
+  }
+
+ private:
+  static const char* hardware_;
+#if defined(DEBUG)
+  static bool initialized_;
+#endif
 };
 
 class TargetCPUFeatures : public AllStatic {
  public:
-  static void InitOnce() {}
-  static void Cleanup() {}
+  static void InitOnce() {
+    HostCPUFeatures::InitOnce();
+  }
+  static void Cleanup() {
+    HostCPUFeatures::Cleanup();
+  }
+
+  static const char* hardware() {
+    return CPU::Id();
+  }
 
   static bool double_truncate_round_supported() {
     return true;
   }
 };
 
 }  // namespace dart
 
 #endif  // VM_CPU_DBC_H_