Support PolicyWatcher with custom loader for testing

remoting/host/policy_watcher.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_HOST_POLICY_WATCHER_H_
 #define REMOTING_HOST_POLICY_WATCHER_H_
 
 #include <memory>
 
 #include "base/callback.h"
@@ skipping 60 matching lines @@
   // When |policy_service| is specified then |file_task_runner| argument is
   // ignored and 1) BrowserThread::UI is used for PolicyUpdatedCallback and
   // PolicyErrorCallback and 2) BrowserThread::FILE is used for reading the
   // policy from files / registry / preferences (although (2) is just an
   // implementation detail and should likely be ignored outside of
   // PolicyWatcher).
   static std::unique_ptr<PolicyWatcher> Create(
       policy::PolicyService* policy_service,
       const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner);
 
+  // Creates a PolicyWatcher from the given loader instead of loading the policy
+  // from the default location.
+  //
+  // This can be used with FakeAsyncPolicyLoader to test policy handling of
+  // other components.
+  static std::unique_ptr<PolicyWatcher> CreateFromPolicyLoaderForTesting(
+      std::unique_ptr<policy::AsyncPolicyLoader> async_policy_loader);
+
  private:
   friend class PolicyWatcherTest;
 
   // Gets Chromoting schema stored inside |owned_schema_registry_|.
   const policy::Schema* GetPolicySchema() const;
 
   // Simplifying wrapper around Schema::Normalize.
   // - Returns false if |dict| is invalid (i.e. contains mistyped policy
   // values).
   // - Returns true if |dict| was valid or got normalized.
@@ skipping 45 matching lines @@
   std::unique_ptr<policy::SchemaRegistry> owned_schema_registry_;
   std::unique_ptr<policy::ConfigurationPolicyProvider> owned_policy_provider_;
   std::unique_ptr<policy::PolicyService> owned_policy_service_;
 
   DISALLOW_COPY_AND_ASSIGN(PolicyWatcher);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_HOST_POLICY_WATCHER_H_