Switch PermissionStatus events to an observer model.

content/browser/permissions/permission_service_impl.h

 // Copyright 2014 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 CONTENT_BROWSER_PERMISSIONS_PERMISSION_SERVICE_IMPL_H_
 #define CONTENT_BROWSER_PERMISSIONS_PERMISSION_SERVICE_IMPL_H_
 
 #include "base/callback.h"
 #include "base/id_map.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "content/browser/permissions/permission_service_context.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "third_party/WebKit/public/platform/modules/permissions/permission.mojom.h"
 #include "url/origin.h"
 
 namespace content {
 
 enum class PermissionType;
 
 // Implements the PermissionService Mojo interface.
 // This service can be created from a RenderFrameHost or a RenderProcessHost.
 // It is owned by a PermissionServiceContext.
 // It receives at PermissionServiceContext instance when created which allows it
 // to have some information about the current context. That enables the service
 // to know whether it can show UI and have knowledge of the associated
 // WebContents for example.
 class PermissionServiceImpl : public blink::mojom::PermissionService {
  public:
+  PermissionServiceImpl(
+      PermissionServiceContext* context,
+      mojo::InterfaceRequest<blink::mojom::PermissionService> request);
   ~PermissionServiceImpl() override;
 
   // Clear pending operations currently run by the service. This will be called
   // by PermissionServiceContext when it will need the service to clear its
   // state for example, if the frame changes.
   void CancelPendingOperations();
 
- protected:
-  friend PermissionServiceContext;
-
-  PermissionServiceImpl(
-      PermissionServiceContext* context,
-      mojo::InterfaceRequest<blink::mojom::PermissionService> request);
-
  private:
   using PermissionStatusCallback =
       base::Callback<void(blink::mojom::PermissionStatus)>;
 
   struct PendingRequest {
     PendingRequest(const RequestPermissionsCallback& callback,
                    int request_count);
     ~PendingRequest();
 
     // Request ID received from the PermissionManager.
     int id;
     RequestPermissionsCallback callback;
     int request_count;
   };
   using RequestsMap = IDMap<std::unique_ptr<PendingRequest>>;
 
-  struct PendingSubscription {
-    PendingSubscription(PermissionType permission,
-                        const url::Origin& origin,
-                        const PermissionStatusCallback& callback);
-    ~PendingSubscription();
-
-    // Subscription ID received from the PermissionManager.
-    int id;
-    PermissionType permission;
-    url::Origin origin;
-    PermissionStatusCallback callback;
-  };
-  using SubscriptionsMap = IDMap<std::unique_ptr<PendingSubscription>>;
-
   // blink::mojom::PermissionService.
   void HasPermission(blink::mojom::PermissionDescriptorPtr permission,
                      const url::Origin& origin,
                      const PermissionStatusCallback& callback) override;
   void RequestPermission(blink::mojom::PermissionDescriptorPtr permission,
                          const url::Origin& origin,
                          bool user_gesture,
                          const PermissionStatusCallback& callback) override;
   void RequestPermissions(
       std::vector<blink::mojom::PermissionDescriptorPtr> permissions,
       const url::Origin& origin,
       bool user_gesture,
       const RequestPermissionsCallback& callback) override;
   void RevokePermission(blink::mojom::PermissionDescriptorPtr permission,
                         const url::Origin& origin,
                         const PermissionStatusCallback& callback) override;
-  void GetNextPermissionChange(
+  void AddPermissionObserver(
       blink::mojom::PermissionDescriptorPtr permission,
       const url::Origin& origin,
       blink::mojom::PermissionStatus last_known_status,
-      const PermissionStatusCallback& callback) override;
+      blink::mojom::PermissionObserverPtr observer) override;
 
   void OnConnectionError();
 
   void OnRequestPermissionResponse(int pending_request_id,
                                    blink::mojom::PermissionStatus status);
   void OnRequestPermissionsResponse(
       int pending_request_id,
       const std::vector<blink::mojom::PermissionStatus>& result);
 
   blink::mojom::PermissionStatus GetPermissionStatus(
       const blink::mojom::PermissionDescriptorPtr& permission,
       const url::Origin& origin);
   blink::mojom::PermissionStatus GetPermissionStatusFromType(
       PermissionType type,
       const url::Origin& origin);
   void ResetPermissionStatus(PermissionType type, const url::Origin& origin);
 
-  void OnPermissionStatusChanged(int pending_subscription_id,
-                                 blink::mojom::PermissionStatus status);
-
   RequestsMap pending_requests_;
-  SubscriptionsMap pending_subscriptions_;
   // context_ owns |this|.
   PermissionServiceContext* context_;
   mojo::Binding<blink::mojom::PermissionService> binding_;
   base::WeakPtrFactory<PermissionServiceImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PermissionServiceImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_PERMISSIONS_PERMISSION_SERVICE_IMPL_H_