Always run PolicyWatcher on UI thread in It2Me host.

remoting/host/policy_hack/policy_watcher.cc

 // Copyright (c) 2012 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.
 
 // Most of this code is copied from:
 //   src/chrome/browser/policy/asynchronous_policy_loader.{h,cc}
 
 #include "remoting/host/policy_hack/policy_watcher.h"
 
 #include "base/bind.h"
@@ skipping 260 matching lines @@
       new policy::PolicyServiceImpl(providers));
 
   policy::PolicyService* borrowed_policy_service = policy_service.get();
   return make_scoped_ptr(new PolicyWatcher(
       policy_service_task_runner, borrowed_policy_service,
       policy_service.Pass(), policy_provider.Pass(), schema_registry.Pass()));
 }
 
 scoped_ptr<PolicyWatcher> PolicyWatcher::Create(
     policy::PolicyService* policy_service,
-    const scoped_refptr<base::SingleThreadTaskRunner>& network_task_runner) {
+    const scoped_refptr<base::SingleThreadTaskRunner>& current_task_runner,
+    const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner) {
+  DCHECK(current_task_runner->BelongsToCurrentThread());

[Łukasz Anforowicz, 2015/01/30 05:35:55]

It might be possible to avoid explicitly passing current_task_runner, by getting
it from MessageLoopProxy::current().  I am not sure if this is desirable
though...

[Sergey Ulanov, 2015/01/30 19:33:45]

base::ThreadTaskRunnerHandle::Get() is the preferred way to get task runner for
current thread. But in remoting host we use AutoThreadTaskRunner and so it needs
to be passed explicitly. Anyway, this parameter is not needed anymore. Removed
it.

+
 #if defined(OS_CHROMEOS)
+  // On Chrome OS the PolicyService is owned by the browser.
   DCHECK(policy_service);
   return make_scoped_ptr(
       new PolicyWatcher(content::BrowserThread::GetMessageLoopProxyForThread(
                             content::BrowserThread::UI),

[Łukasz Anforowicz, 2015/01/30 05:35:55]

This call to GetMessageLoopProxyForThread should probably be replaced with
current_task_runner?  Or maybe with a DCHECK that these two values are equal?

[Sergey Ulanov, 2015/01/30 19:33:45]

removed current_task_runner

                         policy_service, nullptr, nullptr, nullptr));
-#elif defined(OS_WIN)
+#else  // !defined(OS_CHROMEOS)
   DCHECK(!policy_service);
-  // Always read the Chrome policies (even on Chromium) so that policy
-  // enforcement can't be bypassed by running Chromium.
-  // Note that this comment applies to all of Win/Mac/Posix branches below.
-  static const wchar_t kRegistryKey[] = L"SOFTWARE\\Policies\\Google\\Chrome";
-  return PolicyWatcher::CreateFromPolicyLoader(
-      network_task_runner,
-      policy::PolicyLoaderWin::Create(network_task_runner, kRegistryKey));
+
+  // Create platform-specific PolicyLoader. Always read the Chrome policies
+  // (even on Chromium) so that policy enforcement can't be bypassed by running
+  // Chromium.
+  scoped_ptr<policy::AsyncPolicyLoader> policy_loader;
+#if defined(OS_WIN)
+  policy_loader = policy::PolicyLoaderWin::Create(
+      io_task_runner, L"SOFTWARE\\Policies\\Google\\Chrome");
 #elif defined(OS_MACOSX)
   CFStringRef bundle_id = CFSTR("com.google.Chrome");
-  DCHECK(!policy_service);
-  return PolicyWatcher::CreateFromPolicyLoader(
-      network_task_runner,
-      make_scoped_ptr(new policy::PolicyLoaderMac(
-          network_task_runner,
-          policy::PolicyLoaderMac::GetManagedPolicyPath(bundle_id),
-          new MacPreferences(), bundle_id)));
+  policy_loader.reset(new policy::PolicyLoaderMac(
+      io_task_runner,
+      policy::PolicyLoaderMac::GetManagedPolicyPath(bundle_id),
+      new MacPreferences(), bundle_id));
 #elif defined(OS_POSIX) && !defined(OS_ANDROID)
-  DCHECK(!policy_service);
-  static const base::FilePath::CharType kPolicyDir[] =
-      FILE_PATH_LITERAL("/etc/opt/chrome/policies");
-  return PolicyWatcher::CreateFromPolicyLoader(
-      network_task_runner, make_scoped_ptr(new policy::ConfigDirPolicyLoader(
-                               network_task_runner, base::FilePath(kPolicyDir),
-                               policy::POLICY_SCOPE_MACHINE)));
+  policy_loader.reset(new policy::ConfigDirPolicyLoader(
+      io_task_runner,
+      base::FilePath(FILE_PATH_LITERAL("/etc/opt/chrome/policies")),
+      policy::POLICY_SCOPE_MACHINE));
 #else
 #error OS that is not yet supported by PolicyWatcher code.
 #endif
+
+  return PolicyWatcher::CreateFromPolicyLoader(current_task_runner,
+                                               policy_loader.Pass());
+#endif  // !(OS_CHROMEOS)
 }
 
 }  // namespace policy_hack
 }  // namespace remoting