[Media Router] Consistently refer to issue's learn more help page by ID.

chrome/browser/ui/webui/media_router/media_router_ui.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/media_router/media_router_ui.h"
 
 #include <algorithm>
 #include <string>
 #include <utility>
 
@@ skipping 573 matching lines @@
       issue_title = l10n_util::GetStringUTF8(
           IDS_MEDIA_ROUTER_ISSUE_CREATE_ROUTE_TIMEOUT_FOR_DESKTOP);
       break;
     default:
       NOTREACHED();
   }
 
   Issue issue(issue_title, std::string(),
               IssueAction(IssueAction::TYPE_DISMISS),
               std::vector<IssueAction>(), std::string(), Issue::NOTIFICATION,
-              false, std::string());
+              false, -1);
   AddIssue(issue);
 }
 
 void MediaRouterUI::SendIssueForUnableToCast(MediaCastMode cast_mode) {
   // For a generic error, claim a tab error unless it was specifically desktop
   // mirroring.
   std::string issue_title =
       (cast_mode == MediaCastMode::DESKTOP_MIRROR)
           ? l10n_util::GetStringUTF8(
                 IDS_MEDIA_ROUTER_ISSUE_UNABLE_TO_CAST_DESKTOP)
           : l10n_util::GetStringUTF8(
                 IDS_MEDIA_ROUTER_ISSUE_CREATE_ROUTE_TIMEOUT_FOR_TAB);
   AddIssue(Issue(issue_title, std::string(),
                  IssueAction(IssueAction::TYPE_DISMISS),
                  std::vector<IssueAction>(), std::string(), Issue::WARNING,
-                 false, std::string()));
+                 false, -1));
 }
 
 GURL MediaRouterUI::GetFrameURL() const {
   return presentation_request_ ? presentation_request_->frame_url() : GURL();
 }
 
 std::string MediaRouterUI::GetPresentationRequestSourceName() const {
   GURL gurl = GetFrameURL();
   return gurl.SchemeIs(extensions::kExtensionScheme)
              ? GetExtensionName(gurl, extensions::ExtensionRegistry::Get(
@@ skipping 33 matching lines @@
         base::Time::Now() - start_time_);
     start_time_ = base::Time();
   }
 }
 
 void MediaRouterUI::UpdateMaxDialogHeight(int height) {
   handler_->UpdateMaxDialogHeight(height);
 }
 
 }  // namespace media_router