Define PushMessagingApplicationId and replace ad-hoc code.

content/public/browser/push_messaging_application_id.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_PUBLIC_BROWSER_PUSH_MESSAGING_APPLICATION_ID_H_
+#define CONTENT_PUBLIC_BROWSER_PUSH_MESSAGING_APPLICATION_ID_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "content/common/content_export.h"
+#include "url/gurl.h"
+
+namespace content {
+
+// The prefix used for all push messaging application ids.
+CONTENT_EXPORT extern const char kPushMessagingApplicationIdPrefix[];
+
+// Type used to identify an "application" from a Push API perspective.

[johnme, 2014/07/23 12:36:57]

Nit: s/an "application"/a web app/ ?

[Michael van Ouwerkerk, 2014/07/23 15:05:14]

Done.

+struct CONTENT_EXPORT PushMessagingApplicationId {
+ public:
+  static PushMessagingApplicationId Parse(const std::string& id);
+
+  PushMessagingApplicationId()
+      : origin(GURL::EmptyGURL()), service_worker_registration_id(-1) {}
+  PushMessagingApplicationId(const GURL& origin,
+                             int64 service_worker_registration_id)
+      : origin(origin),
+        service_worker_registration_id(service_worker_registration_id) {}
+
+  bool is_valid() {

[johnme, 2014/07/23 12:36:57]

Nit: this isn't a simple getter, so IIRC the definition should go in the .cc

[Michael van Ouwerkerk, 2014/07/23 15:05:14]

Done.

+    return origin.is_valid() && origin.GetOrigin() == origin &&
+           service_worker_registration_id >= 0;
+  }
+
+  std::string ToString();
+
+  GURL origin;

[johnme, 2014/07/23 12:36:57]

Perhaps these should be immutable? You might even do the validity check in the
2nd constructor, then you could have is_valid() { return
service_worker_registration_id >= 0; }

[Michael van Ouwerkerk, 2014/07/23 15:05:14]

Ok they're const now.

+  int64 service_worker_registration_id;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_PUSH_MESSAGING_APPLICATION_ID_H_