Changing policy while Chrome is running should refresh preferences without relaunching

chrome/browser/configuration_policy_provider_win.cc

Index: chrome/browser/configuration_policy_provider_win.cc
diff --git a/chrome/browser/configuration_policy_provider_win.cc b/chrome/browser/configuration_policy_provider_win.cc
index 61d264ce7abbb29db46e9bacd4fca2c28b52e435..b70f01dd9a855ce64cadaf943dd4474112c5057e 100644
--- a/chrome/browser/configuration_policy_provider_win.cc
+++ b/chrome/browser/configuration_policy_provider_win.cc
@@ -4,18 +4,56 @@
 
 #include "chrome/browser/configuration_policy_provider_win.h"
 
+#include <userenv.h>
+
 #include <algorithm>
 
 #include "base/logging.h"
+#include "base/object_watcher.h"
 #include "base/registry.h"
 #include "base/scoped_ptr.h"
 #include "base/string_piece.h"
 #include "base/sys_string_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
+#include "base/waitable_event.h"
 #include "chrome/common/policy_constants.h"
 
+ConfigurationPolicyProviderWin::GroupPolicyChangeWatcher::
+    GroupPolicyChangeWatcher(ConfigurationPolicyProvider* provider)
+        : provider_(provider),
+          user_policy_changed_event_(false, false),
+          machine_policy_changed_event_(false, false) {
+  CHECK(RegisterGPNotification(user_policy_changed_event_.handle(), false));
+  CHECK(RegisterGPNotification(machine_policy_changed_event_.handle(), true));
+  user_policy_watcher_.StartWatching(
+      user_policy_changed_event_.handle(),
+      this);
+  machine_policy_watcher_.StartWatching(
+      machine_policy_changed_event_.handle(),
+      this);
+}
+
+void ConfigurationPolicyProviderWin::GroupPolicyChangeWatcher::
+    OnObjectSignaled(HANDLE object) {
+  provider_->NotifyStoreOfPolicyChange();
+  if (object == user_policy_changed_event_.handle()) {
+    user_policy_watcher_.StartWatching(
+        user_policy_changed_event_.handle(),
+        this);
+  } else if (object == machine_policy_changed_event_.handle()) {
+    machine_policy_watcher_.StartWatching(
+        machine_policy_changed_event_.handle(),
+        this);
+  } else {
+    // This method should only be called as a result of signals
+    // to the user- and machine-policy handle watchers.
+    NOTREACHED();
+  }
+}
+
 ConfigurationPolicyProviderWin::ConfigurationPolicyProviderWin() {
+  watcher_.reset(new GroupPolicyChangeWatcher(this));
 }
 
 bool ConfigurationPolicyProviderWin::GetRegistryPolicyString(