[Extensions] Make Event::restrict_to_browser_context const.

chrome/browser/extensions/api/identity/web_auth_flow.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.
 
 #include "chrome/browser/extensions/api/identity/web_auth_flow.h"
 
 #include <utility>
 
 #include "base/base64.h"
 #include "base/location.h"
@@ skipping 77 matching lines @@
 
   // identityPrivate.onWebFlowRequest(app_window_key, provider_url_, mode_)
   std::unique_ptr<base::ListValue> args(new base::ListValue());
   args->AppendString(app_window_key_);
   args->AppendString(provider_url_.spec());
   if (mode_ == WebAuthFlow::INTERACTIVE)
     args->AppendString("interactive");
   else
     args->AppendString("silent");
 
-  std::unique_ptr<Event> event(new Event(
-      events::IDENTITY_PRIVATE_ON_WEB_FLOW_REQUEST,
-      identity_private::OnWebFlowRequest::kEventName, std::move(args)));
-  event->restrict_to_browser_context = profile_;
+  auto event =
+      base::MakeUnique<Event>(events::IDENTITY_PRIVATE_ON_WEB_FLOW_REQUEST,
+                              identity_private::OnWebFlowRequest::kEventName,
+                              std::move(args), profile_);
   ExtensionSystem* system = ExtensionSystem::Get(profile_);
 
   extensions::ComponentLoader* component_loader =
       system->extension_service()->component_loader();
   if (!component_loader->Exists(extension_misc::kIdentityApiUiAppId)) {
     component_loader->Add(
         IDR_IDENTITY_API_SCOPE_APPROVAL_MANIFEST,
         base::FilePath(FILE_PATH_LITERAL("identity_scope_approval_dialog")));
   }
 
@@ skipping 107 matching lines @@
         "identity", "WebAuthFlow", this, "DidFinishNavigationFailure",
         "response_code",
         navigation_handle->GetResponseHeaders()->response_code());
   }
 
   if (failed && delegate_)
     delegate_->OnAuthFlowFailure(LOAD_FAILED);
 }
 
 }  // namespace extensions