Implement basic mojo Permission service and use it for Geolocation.

content/browser/permissions/permission_service_context.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_CONTEXT_H_
+#define CONTENT_BROWSER_PERMISSIONS_PERMISSION_SERVICE_CONTEXT_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_vector.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "mojo/public/cpp/bindings/interface_request.h"
+
+namespace content {
+
+class PermissionService;
+class PermissionServiceImpl;
+class RenderFrameHost;
+
+// Provides information to a PermissionService. It is used by the
+// PermissionService to handle request permission UI.
+// The RenderFrameHost creates an instance when setting up the Permission mojo

[blundell, 2014/11/14 14:41:59]

This comment is out-of-date.

[mlamouri (slow - plz ping), 2014/11/14 16:14:45]

Acknowledged.

+// service and then passes ownership to the service.
+class PermissionServiceContext : public WebContentsObserver {
+ public:
+  void CreateService(mojo::InterfaceRequest<PermissionService> request);
+
+  // Called by a PermissionService identified as |service| when it has a
+  // connection error in order to get unregistered and killed.
+  void ServiceHadConnectionError(PermissionServiceImpl* service);
+
+ public:
+  explicit PermissionServiceContext(RenderFrameHost* render_frame_host);

[blundell, 2014/11/14 14:41:59]

these should be at the top, and you can kill the duplicate "public:".

[mlamouri (slow - plz ping), 2014/11/14 16:14:45]

Oups :)

+  virtual ~PermissionServiceContext();
+
+  // WebContentsObserver
+  void RenderFrameDeleted(RenderFrameHost* render_frame_host) override;

[blundell, 2014/11/14 14:41:59]

nit: I would make these private to make it clear they're not part of the public
interface.

[mlamouri (slow - plz ping), 2014/11/14 16:14:45]

Done.

+  void DidNavigateAnyFrame(RenderFrameHost* render_frame_host,
+                           const LoadCommittedDetails& details,
+                           const FrameNavigateParams& params) override;
+
+ private:
+  void CancelPendingRequests(RenderFrameHost*) const;
+
+  RenderFrameHost* render_frame_host_;
+  ScopedVector<PermissionServiceImpl> services_;
+
+  DISALLOW_COPY_AND_ASSIGN(PermissionServiceContext);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_PERMISSIONS_PERMISSION_SERVICE_CONTEXT_H_