[Media Router] Convert MediaRouter to use GURL for presentation URLs.

chrome/browser/media/router/presentation_request.h

 // Copyright 2015 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 CHROME_BROWSER_MEDIA_ROUTER_PRESENTATION_REQUEST_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_PRESENTATION_REQUEST_H_
 
 #include <string>
 #include <vector>
 
 #include "chrome/browser/media/router/media_source.h"
 #include "chrome/browser/media/router/render_frame_host_id.h"
 #include "url/gurl.h"
 
 namespace media_router {
 
 // Represents a presentation request made from a render frame. Contains the
 // presentation URL of the request, and information on the originating frame.
 class PresentationRequest {
  public:
   PresentationRequest(const RenderFrameHostId& render_frame_host_id,
-                      const std::vector<std::string>& presentation_urls,
+                      const std::vector<GURL>& presentation_urls,
                       const GURL& frame_url);
   PresentationRequest(const PresentationRequest& other);
   ~PresentationRequest();
 
   bool Equals(const PresentationRequest& other) const;
 
   // Helper method to get the MediaSources for |presentation_urls_|.
   std::vector<MediaSource> GetMediaSources() const;
 
   const RenderFrameHostId& render_frame_host_id() const {
     return render_frame_host_id_;
   }
   // TODO(crbug.com/627655): Use multiple URLs.
-  const std::string& presentation_url() const { return presentation_urls_[0]; }
+  const GURL& presentation_url() const { return presentation_urls_[0]; }
   const GURL& frame_url() const { return frame_url_; }
 
  private:
   // ID of RenderFrameHost that initiated the request.
   const RenderFrameHostId render_frame_host_id_;
 
   // URLs of presentation.
-  const std::vector<std::string> presentation_urls_;
+  const std::vector<GURL> presentation_urls_;
 
   // URL of frame from which the request was initiated.
   const GURL frame_url_;
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_PRESENTATION_REQUEST_H_