[cronet] Add mechanism for restarting CronetEnvironment

components/cronet/ios/Cronet.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.
 
 #import <Foundation/Foundation.h>
 
 #include "bidirectional_stream_c.h"
 
 // TODO(mef): Remove this header after transition to bidirectional_stream_c.h
 // See crbug.com/650462 for details.
@@ skipping 63 matching lines @@
 // method with nil block.
 + (void)setRequestFilterBlock:(RequestFilterBlock)block;
 
 // Starts CronetEngine. It is recommended to call this method on the application
 // main thread. If the method is called on any thread other than the main one,
 // the method will internally try to execute synchronously using the main GCD
 // queue. Please make sure that the main thread is not blocked by a job
 // that calls this method; otherwise, a deadlock can occur.
 + (void)start;
 
++ (void)shutdown;

[mef, 2017/04/26 22:19:41]

// need comment.

[lilyhoughton, 2017/04/27 13:53:39]

Actually, just removing this.

+
 // Registers Cronet as HttpProtocol Handler. Once registered, Cronet intercepts
 // and handles all requests made through NSURLConnection and shared
 // NSURLSession.
 // This method must be called after |start|.
 + (void)registerHttpProtocolHandler;
 
 // Unregister Cronet as HttpProtocol Handler. This means that Cronet will stop
 // intercepting requests, however, it won't tear down the Cronet environment.
 // This method must be called after |start|.
 + (void)unregisterHttpProtocolHandler;
@@ skipping 38 matching lines @@
 
 // Sets Host Resolver Rules for testing.
 // This method must be called after |start| has been called.
 + (void)setHostResolverRulesForTesting:(NSString*)hostResolverRulesForTesting;
 
 // Enables TestCertVerifier which accepts all certificates for testing.
 // This method only has any effect before |start| is called.
 + (void)enableTestCertVerifierForTesting;
 
 @end