Add the copresence component.

components/copresence/interface/copresence_delegate.h

Index: components/copresence/interface/copresence_delegate.h
diff --git a/components/copresence/interface/copresence_delegate.h b/components/copresence/interface/copresence_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..9c627c9f24ca8d23b6f215a04fe796008ad8abed
--- /dev/null
+++ b/components/copresence/interface/copresence_delegate.h
@@ -0,0 +1,52 @@
+// 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 COMPONENTS_COPRESENCE_INTERFACE_COPRESENCE_DELGATE_H_
+#define COMPONENTS_COPRESENCE_INTERFACE_COPRESENCE_DELGATE_H_
+
+#include <string>
+
+#include "base/callback_forward.h"
+#include "components/copresence/proto/rpcs.pb.h"
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+namespace copresence {
+
+// This enum (and the following callback) aren't strictly a part of this
+// interface, but they are needed by other methods in CopresenceClient to
+// talk back to the user of Copresence, hence they seem to belong here.
+enum CopresenceStatus { SUCCESS, FAIL };
+
+// Callback type to send a status.
+typedef base::Callback<void(CopresenceStatus)> StatusCallback;
+
+// A delegate interface for the users of Copresence.
+class CopresenceDelegate {
+ public:
+  // This method will be called when we have subscribed messages that need to
+  // be sent back their respective apps.
+  virtual void HandleMessages(
+      const std::string& app_id,
+      const std::string& subscription_id,
+      const std::vector<copresence::Message>& message) = 0;
+
+  // This is used by use to be able to send HttpPosts to the copresence server.
+  virtual net::URLRequestContextGetter* GetRequestContext() const = 0;
+
+  // Only needed for analytics and debugging on the server, can be empty.
+  virtual const std::string GetPlatformVersionString() const = 0;
+
+  // Methods to set and and get our device ID. This needs to be saved to
+  // persistent storage to avoid flooding the Copresence server with generate
+  // id requests.
+  virtual const std::string GetDeviceId() const = 0;
+  virtual void SaveDeviceId(const std::string& device_id) = 0;
+};
+
+}  // namespace copresence
+
+#endif  // COMPONENTS_COPRESENCE_INTERFACE_COPRESENCE_DELGATE_H_