Add a Physical Web data source

ios/chrome/common/physical_web/ios_chrome_physical_web_data_source.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 IOS_CHROME_COMMON_PHYSICAL_WEB_IOS_CHROME_PHYSICAL_WEB_DATA_SOURCE_H_
+#define IOS_CHROME_COMMON_PHYSICAL_WEB_IOS_CHROME_PHYSICAL_WEB_DATA_SOURCE_H_
+
+#include "base/macros.h"
+#import "base/mac/scoped_nsobject.h"
+#include "components/physical_web/data_source/physical_web_data_source.h"
+
+namespace base {
+class ListValue;
+}
+
+@class PhysicalWebScanner;
+
+// iOS implementation of PhysicalWebDataSource
+class IOSChromePhysicalWebDataSource : public PhysicalWebDataSource {
+ public:
+  IOSChromePhysicalWebDataSource();
+  ~IOSChromePhysicalWebDataSource() override;
+
+  // Starts scanning for Physical Web URLs. If |network_request_enabled| is
+  // true, discovered URLs will be sent to a resolution service.
+  void StartDiscovery(bool network_request_enabled) override;
+
+  // Stops scanning for Physical Web URLs and clears cached URL content.
+  void StopDiscovery() override;
+
+  // Returns a list of resolved URLs and associated page metadata. If network
+  // requests are disabled, the list will be empty.
+  std::unique_ptr<base::ListValue> GetMetadata() override;
+
+  // Returns boolean |true| if network requests are disabled and there are one
+  // or more discovered URLs that have not been sent to the resolution service.
+  bool HasUnresolvedDiscoveries() override;
+
+ private:
+  // Scanner for nearby Physical Web URL devices.
+  base::scoped_nsobject<PhysicalWebScanner> scanner_;
+
+  DISALLOW_COPY_AND_ASSIGN(IOSChromePhysicalWebDataSource);
+};
+
+#endif  // IOS_CHROME_COMMON_PHYSICAL_WEB_IOS_CHROME_PHYSICAL_WEB_DATA_SOURCE_H_