Convert network hints to Mojo

components/network_hints/browser/network_hints_message_filter.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 "components/network_hints/browser/network_hints_message_filter.h"
-
-#include "base/logging.h"
-#include "base/macros.h"
-#include "components/network_hints/common/network_hints_common.h"
-#include "components/network_hints/common/network_hints_messages.h"
-#include "ipc/ipc_message_macros.h"
-#include "net/base/address_list.h"
-#include "net/base/net_errors.h"
-#include "net/dns/host_resolver.h"
-#include "net/dns/single_request_host_resolver.h"
-#include "url/gurl.h"
-
-namespace network_hints {
-
-namespace {
-
-const int kDefaultPort = 80;
-
-class DnsLookupRequest {
- public:
-  DnsLookupRequest(net::HostResolver* host_resolver,
-                   const std::string& hostname)
-      : hostname_(hostname),
-        resolver_(host_resolver) {
-  }
-
-  // Return underlying network resolver status.
-  // net::OK ==> Host was found synchronously.
-  // net:ERR_IO_PENDING ==> Network will callback later with result.
-  // anything else ==> Host was not found synchronously.
-  int Start() {
-    net::HostResolver::RequestInfo resolve_info(
-        net::HostPortPair(hostname_, kDefaultPort));
-
-    // Make a note that this is a speculative resolve request. This allows
-    // separating it from real navigations in the observer's callback, and
-    // lets the HostResolver know it can be de-prioritized.
-    resolve_info.set_is_speculative(true);
-    return resolver_.Resolve(
-        resolve_info,
-        net::DEFAULT_PRIORITY,
-        &addresses_,
-        base::Bind(&DnsLookupRequest::OnLookupFinished, base::Owned(this)),
-        net::BoundNetLog());
-  }
-
- private:
-  void OnLookupFinished(int result) {
-    VLOG(2) << __FUNCTION__ << ": " << hostname_ << ", result=" << result;
-  }
-
-  const std::string hostname_;
-  net::SingleRequestHostResolver resolver_;
-  net::AddressList addresses_;
-
-  DISALLOW_COPY_AND_ASSIGN(DnsLookupRequest);
-};
-
-}  // namespace
-
-NetworkHintsMessageFilter::NetworkHintsMessageFilter(
-    net::HostResolver* host_resolver)
-    : content::BrowserMessageFilter(NetworkHintsMsgStart),
-      host_resolver_(host_resolver) {
-  DCHECK(host_resolver_);
-}
-
-NetworkHintsMessageFilter::~NetworkHintsMessageFilter() {
-}
-
-bool NetworkHintsMessageFilter::OnMessageReceived(const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(NetworkHintsMessageFilter, message)
-    IPC_MESSAGE_HANDLER(NetworkHintsMsg_DNSPrefetch, OnDnsPrefetch)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void NetworkHintsMessageFilter::OnDnsPrefetch(
-    const LookupRequest& lookup_request) {
-  DCHECK(host_resolver_);
-  for (const std::string& hostname : lookup_request.hostname_list) {
-    DnsLookupRequest* request = new DnsLookupRequest(host_resolver_, hostname);
-    // Note: DnsLookupRequest will be freed by the base::Owned call when
-    // resolving has completed.
-    request->Start();
-  }
-}
-
-}  // namespace network_hints