Add AssertNoURLRequests() to URLRequestContext subclass destructors.

chrome/browser/io_thread.cc

 // Copyright (c) 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.
 
 #include "chrome/browser/io_thread.h"
 
 #include <vector>
 
 #include "base/base64.h"
 #include "base/bind.h"
@@ skipping 141 matching lines @@
 class SystemURLRequestContext : public net::URLRequestContext {
  public:
   SystemURLRequestContext() {
 #if defined(USE_NSS) || defined(OS_IOS)
     net::SetURLRequestContextForNSSHttpIO(this);
 #endif
   }
 
  private:
   virtual ~SystemURLRequestContext() {
+    AssertNoURLRequests();

[Ryan Sleevi, 2014/07/10 16:49:19]

Seems like this should go second, right?

After all, what if line 164 cancels requests?

[Johnny, 2014/07/10 16:58:28]

That'd be a violation of the URLRequestContext lifetime invariant. URLRequests
must keep a URLRequestContext alive, not the other way around, no?

(It doesn't, btw. Just sets a global).

 #if defined(USE_NSS) || defined(OS_IOS)
     net::SetURLRequestContextForNSSHttpIO(NULL);
 #endif
   }
 };
 
 scoped_ptr<net::HostResolver> CreateGlobalHostResolver(net::NetLog* net_log) {
   TRACE_EVENT0("startup", "IOThread::CreateGlobalHostResolver");
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
 
@@ skipping 1195 matching lines @@
   net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
   for (size_t i = 0; i < supported_versions.size(); ++i) {
     net::QuicVersion version = supported_versions[i];
     if (net::QuicVersionToString(version) == quic_version) {
       return version;
     }
   }
 
   return net::QUIC_VERSION_UNSUPPORTED;
 }