Use a service to create device management backends.

chrome/test/testing_profile.h

Index: chrome/test/testing_profile.h
diff --git a/chrome/test/testing_profile.h b/chrome/test/testing_profile.h
index 126dfcf66829947435dd7b1f5b6679c35cb7a632..dbfa2667ae1eea4313ede08754e27586551d8920 100644
--- a/chrome/test/testing_profile.h
+++ b/chrome/test/testing_profile.h
@@ -308,10 +308,7 @@ class TestingProfile : public Profile {
   virtual ChromeBlobStorageContext* GetBlobStorageContext() { return NULL; }
   virtual ExtensionInfoMap* GetExtensionInfoMap() { return NULL; }
   virtual PromoCounter* GetInstantPromoCounter() { return NULL; }
-  virtual policy::DeviceManagementPolicyProvider*
-      GetDeviceManagementPolicyProvider() {
-    return NULL;
-  }
+  virtual policy::ProfilePolicyContext* GetPolicyContext() { return NULL; }
 
  protected:
   base::Time start_time_;