Enable NPAPI if policy has plugin policies.

chrome/browser/plugins/plugin_policy_handler.h

+// Copyright 2013 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 CHROME_BROWSER_PLUGINS_PLUGIN_POLICY_HANDLER_H_
+#define CHROME_BROWSER_PLUGINS_PLUGIN_POLICY_HANDLER_H_
+
+#include "components/policy/core/browser/configuration_policy_handler.h"
+
+class PrefValueMap;
+
+namespace base {
+class Value;
+}
+
+namespace policy {
+
+class PolicyErrorMap;
+class PolicyMap;
+
+// ConfigurationPolicyHandler for the plugin policies that re-enable NPAPI.
+class PluginPolicyHandler : public TypeCheckingPolicyHandler {
+ public:
+  PluginPolicyHandler(const char* policy_name,
+                      const char* pref_path,
+                      base::Value::Type value_type);
+
+  ~PluginPolicyHandler() override;
+
+  // ConfigurationPolicyHandler methods:
+  void ApplyPolicySettings(const PolicyMap& policies,
+                           PrefValueMap* prefs) override;
+
+ private:
+  // The DictionaryValue path of the preference the policy maps to.
+  const char* pref_path_;
+
+  DISALLOW_COPY_AND_ASSIGN(PluginPolicyHandler);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_PLUGINS_PLUGIN_POLICY_HANDLER_H_