Revert of Remove obsolete PauseableHttpProtocolHandler class.

ios/net/crn_http_protocol_handler.h

 // Copyright 2012 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_NET_CRN_HTTP_PROTOCOL_HANDLER_H_
 #define IOS_NET_CRN_HTTP_PROTOCOL_HANDLER_H_
 
 #import <Foundation/Foundation.h>
 
 namespace net {
@@ skipping 22 matching lines @@
 
 }  // namespace net
 
 // Custom NSURLProtocol handling HTTP and HTTPS requests.
 // The HttpProtocolHandler is registered as a NSURLProtocol in the iOS system.
 // This protocol is called for each NSURLRequest. This allows handling the
 // requests issued by UIWebView using our own network stack.
 @interface CRNHTTPProtocolHandler : NSURLProtocol
 @end
 
+// Custom NSURLProtocol handling HTTP and HTTPS requests.
+// The HttpProtocolHandler is registered as a NSURLProtocol in the iOS system.
+// This protocol is called for each NSURLRequest. This allows handling the
+// requests issued by UIWebView using our own network stack. This protocol
+// handler implements iOS 8 NSURLProtocol pause/resume semantics, in which
+// |startLoading| means "start or resume" and |stopLoading| means "pause".
+@interface CRNPauseableHTTPProtocolHandler : CRNHTTPProtocolHandler
+@end
+
 #endif  // IOS_NET_CRN_HTTP_PROTOCOL_HANDLER_H_