Change HostResolver::Resolve() to take an std::unique_ptr<Request>* rather than a RequestHandle*

extensions/browser/api/dns/dns_api.cc

 // Copyright 2014 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 "extensions/browser/api/dns/dns_api.h"
 
 #include "base/bind.h"
 #include "base/values.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/resource_context.h"
 #include "extensions/browser/api/dns/host_resolver_wrapper.h"
 #include "extensions/common/api/dns.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/net_errors.h"
 #include "net/log/net_log.h"
 
 using content::BrowserThread;
 using extensions::api::dns::ResolveCallbackResolveInfo;
 
 namespace Resolve = extensions::api::dns::Resolve;
 
 namespace extensions {
 
 DnsResolveFunction::DnsResolveFunction()
-    : resource_context_(NULL),
-      response_(false),
-      request_handle_(new net::HostResolver::RequestHandle()),
-      addresses_(new net::AddressList) {}
+    : resource_context_(), response_(false), addresses_(new net::AddressList) {}
 
 DnsResolveFunction::~DnsResolveFunction() {}
 
 bool DnsResolveFunction::RunAsync() {
   std::unique_ptr<Resolve::Params> params(Resolve::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
 
   hostname_ = params->hostname;
   resource_context_ = browser_context()->GetResourceContext();
 
@@ skipping 13 matching lines @@
   DCHECK(host_resolver);
 
   // Yes, we are passing zero as the port. There are some interesting but not
   // presently relevant reasons why HostResolver asks for the port of the
   // hostname you'd like to resolve, even though it doesn't use that value in
   // determining its answer.
   net::HostPortPair host_port_pair(hostname_, 0);
 
   net::HostResolver::RequestInfo request_info(host_port_pair);
   int resolve_result = host_resolver->Resolve(
-      request_info,
-      net::DEFAULT_PRIORITY,
-      addresses_.get(),
-      base::Bind(&DnsResolveFunction::OnLookupFinished, this),
-      request_handle_.get(),
+      request_info, net::DEFAULT_PRIORITY, addresses_.get(),
+      base::Bind(&DnsResolveFunction::OnLookupFinished, this), &request_,
       net::BoundNetLog());
 
   // Balanced in OnLookupFinished.
   AddRef();
 
   if (resolve_result != net::ERR_IO_PENDING)
     OnLookupFinished(resolve_result);
 }
 
 void DnsResolveFunction::RespondOnUIThread() {
@@ skipping 16 matching lines @@
   bool post_task_result = BrowserThread::PostTask(
       BrowserThread::UI,
       FROM_HERE,
       base::Bind(&DnsResolveFunction::RespondOnUIThread, this));
   DCHECK(post_task_result);
 
   Release();  // Added in WorkOnIOThread().
 }
 
 }  // namespace extensions