DBC: Enable CpuInfo test

runtime/vm/cpu_dbc.h

Index: runtime/vm/cpu_dbc.h
diff --git a/runtime/vm/cpu_dbc.h b/runtime/vm/cpu_dbc.h
index b437beb36c3ae2922dd6511e5c1fcb9572ea2109..486acdb7684cd4c35f44a0fefbfc28caa570d8a8 100644
--- a/runtime/vm/cpu_dbc.h
+++ b/runtime/vm/cpu_dbc.h
@@ -12,13 +12,33 @@ 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;