Replace deprecated calls to GetMetadata in Physical Web omnibox provider

components/omnibox/browser/physical_web_node.h

 // Copyright 2016 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_OMNIBOX_BROWSER_PHYSICAL_WEB_NODE_H_
 #define COMPONENTS_OMNIBOX_BROWSER_PHYSICAL_WEB_NODE_H_
 
 #include "components/bookmarks/browser/titled_url_node.h"
 #include "url/gurl.h"
 
-namespace base {
-class DictionaryValue;
+namespace physical_web {
+struct Metadata;
 }
 
 class PhysicalWebNode : public bookmarks::TitledUrlNode {
  public:
-  explicit PhysicalWebNode(const base::DictionaryValue& metadata_item);
+  explicit PhysicalWebNode(const physical_web::Metadata& metadata_item);
   ~PhysicalWebNode() override;
 
   // TitledUrlNode
   const base::string16& GetTitledUrlNodeTitle() const override;
   const GURL& GetTitledUrlNodeUrl() const override;
 
  private:
   base::string16 node_title_;
   GURL node_url_;
 };
 
 #endif  // COMPONENTS_OMNIBOX_BROWSER_PHYSICAL_WEB_NODE_H_