Removing FakePolicyWatcher and introducing FakeAsyncPolicyLoader.

components/policy/core/common/fake_async_policy_loader.h

Index: components/policy/core/common/fake_async_policy_loader.h
diff --git a/components/policy/core/common/fake_async_policy_loader.h b/components/policy/core/common/fake_async_policy_loader.h
new file mode 100644
index 0000000000000000000000000000000000000000..b5e69d94d2d0238b015f8eea9aba50ca72b8f934
--- /dev/null
+++ b/components/policy/core/common/fake_async_policy_loader.h
@@ -0,0 +1,50 @@
+// 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 COMPONENTS_POLICY_CORE_COMMON_FAKE_ASYNC_POLICY_LOADER_H_
+#define COMPONENTS_POLICY_CORE_COMMON_FAKE_ASYNC_POLICY_LOADER_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/sequenced_task_runner.h"

[Sergey Ulanov, 2015/01/23 18:29:11]

nit: Don't need this include in the header. SequencedTaskRunner can be
forward-declared.

[Łukasz Anforowicz, 2015/01/23 19:24:45]

This is tricky.  With a forward-declaration, all .cc files using this header
will in practice have to include this.  Oh, wait... this error from .cc file
(when just passing the untouched sequenced_task_runner value) is just telling me
that I should be passing scoped_refptr by const-ref, rather than by value.  This
required to also make the change in async_policy_loader.h (otoh, I limited the
change just to the constructor, even though other scoped_refptr-s here could
also be passed by const-ref).

OTOH, I see that I still have to include sequenced_task_runner in
fake_async_policy_loader.cc, because I need the full declaration when calling
PostTask on the runner.

[Sergey Ulanov, 2015/01/23 22:24:40]

Passing scoped_refptr<> may be a bit less efficient than passing them by
const-ref, but it's not a big problem. And yes, you will need to include
sequenced_task_runner.h in .cc files that pass the value. It's still better to
have this file included in several .cc files instead of here, in the header.

+#include "components/policy/core/common/async_policy_loader.h"
+#include "components/policy/core/common/policy_bundle.h"
+
+namespace policy {
+
+// Fake AsyncPolicyLoader for testing with test-controlled policies.
+//
+// Typical test code would populate the policy contents via calls to
+// ClearPolicies and AddPolicies and then notify the rest of the policy
+// subsystem of the changes by calling PostReloadOnBackgroundThread.
+class FakeAsyncPolicyLoader : public AsyncPolicyLoader {
+ public:
+  explicit FakeAsyncPolicyLoader(
+      scoped_refptr<base::SequencedTaskRunner> task_runner);
+
+  // Implementation of virtual methods from AsyncPolicyLoader base class.
+  scoped_ptr<PolicyBundle> Load() override;
+  void InitOnBackgroundThread() override;
+
+  // Provides content for the simulated / faked policies.
+  void SetPolicies(const PolicyBundle& policy_bundle);
+
+  // Notifies the rest of the policy subsystem that policy contents have
+  // changed.  This simulates / fakes a notification that normally would be
+  // triggered by a FilePathWatcher or (registry)ObjectWatcher in a real loader.
+  //
+  // See AsyncPolicyLoader::Reload method for description of the |force|
+  // parameter.
+  void PostReloadOnBackgroundThread(bool force);
+
+ private:
+  PolicyBundle policy_bundle_;
+
+  DISALLOW_COPY_AND_ASSIGN(FakeAsyncPolicyLoader);
+};
+
+}  // namespace policy
+
+#endif  // COMPONENTS_POLICY_CORE_COMMON_FAKE_ASYNC_POLICY_LOADER_H_