Fixes hidden "Set Default Browser" button when group policy is enabled

chrome/browser/ui/webui/settings/settings_default_browser_handler.cc

 // 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.
 
 #include "chrome/browser/ui/webui/settings/settings_default_browser_handler.h"
 
 #include "base/bind.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/common/pref_names.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/web_ui.h"
 
 namespace settings {
 
+namespace {
+
+bool IsDisabledByPolicy(const BooleanPrefMember& pref) {
+  return pref.IsManaged() && !pref.GetValue();
+}
+
+}  // namespace
+
 DefaultBrowserHandler::DefaultBrowserHandler(content::WebUI* webui)
     : default_browser_worker_(new shell_integration::DefaultBrowserWorker(
           this,
           /*delete_observer=*/false)) {
   default_browser_policy_.Init(
       prefs::kDefaultBrowserSettingEnabled, g_browser_process->local_state(),
       base::Bind(&DefaultBrowserHandler::RequestDefaultBrowserState,
                  base::Unretained(this), nullptr));
 }
 
@@ skipping 21 matching lines @@
     // Notify the user in the future if Chrome ceases to be the user's chosen
     // default browser.
     Profile::FromWebUI(web_ui())->GetPrefs()->SetBoolean(
         prefs::kCheckDefaultBrowser, true);
   }
 
   base::FundamentalValue is_default(state ==
                                     shell_integration::STATE_IS_DEFAULT);
   base::FundamentalValue can_be_default(
       state != shell_integration::STATE_UNKNOWN &&
-      !default_browser_policy_.IsManaged() &&
+      !IsDisabledByPolicy(default_browser_policy_) &&
       shell_integration::CanSetAsDefaultBrowser() !=
           shell_integration::SET_DEFAULT_NOT_ALLOWED);
 
   web_ui()->CallJavascriptFunction("Settings.updateDefaultBrowserState",
                                    is_default, can_be_default);
 }
 
 void DefaultBrowserHandler::RequestDefaultBrowserState(
     const base::ListValue* /*args*/) {
   default_browser_worker_->StartCheckIsDefault();
 }
 
 void DefaultBrowserHandler::SetAsDefaultBrowser(const base::ListValue* args) {
-  CHECK(!default_browser_policy_.IsManaged());
+  CHECK(!IsDisabledByPolicy(default_browser_policy_));
 
   default_browser_worker_->StartSetAsDefault();
 
   // If the user attempted to make Chrome the default browser, notify
   // them when this changes.
   Profile::FromWebUI(web_ui())->GetPrefs()->SetBoolean(
       prefs::kCheckDefaultBrowser, true);
 }
 
 }  // namespace settings