[iOS] Upstream physical web classes.

ios/chrome/common/physical_web/physical_web_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 IOS_CHROME_COMMON_PHYSICAL_WEB_PHYSICAL_WEB_REQUEST_H_
+#define IOS_CHROME_COMMON_PHYSICAL_WEB_PHYSICAL_WEB_REQUEST_H_
+
+#import <Foundation/Foundation.h>
+
+#import "ios/chrome/common/physical_web/physical_web_types.h"
+
+// This class will perform a metadata service web request to expand the given
+// URL and return the metadata of the web page such as the title.
+
+@interface PhysicalWebRequest : NSObject
+
+// Initializes a metadata service web request with information about the
+// physical web device.
+- (instancetype)initWithDevice:(PhysicalWebDevice*)device
+    NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+// Starts the request and call the given |block| when finished.
+// |block| should not be nil.
+// If an error occurred, the block will be called with a non-nil error.
+// When no error occurred, the result will be available in a PhysicalWebDevice
+// data structure.
+- (void)start:(physical_web::RequestFinishedBlock)block;
+
+// Cancels the request.
+- (void)cancel;
+
+@end
+
+#endif  // IOS_CHROME_COMMON_PHYSICAL_WEB_PHYSICAL_WEB_REQUEST_H_