NQE: Exclude network observations from private networks

net/nqe/network_quality_estimator_util.cc

Index: net/nqe/network_quality_estimator_util.cc
diff --git a/net/nqe/network_quality_estimator_util.cc b/net/nqe/network_quality_estimator_util.cc
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+++ b/net/nqe/network_quality_estimator_util.cc
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+// Copyright 2017 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 "net/nqe/network_quality_estimator_util.h"
+
+#include "net/base/address_list.h"
+#include "net/base/host_port_pair.h"
+#include "net/base/ip_address.h"
+#include "net/base/ip_endpoint.h"
+#include "net/base/net_errors.h"
+#include "net/dns/host_resolver.h"
+
+namespace net {
+
+namespace nqe {
+
+namespace internal {
+
+bool IsPrivateHost(HostResolver* host_resolver,
+                   const HostPortPair& host_port_pair,
+                   const NetLogWithSource& net_log) {
+  // Try resolving |host_port_pair.host()| synchronously.
+  HostResolver::RequestInfo resolve_info(host_port_pair);
+  resolve_info.set_allow_cached_response(true);
+  AddressList addresses;
+  // Resolve synchronously using the resolver's cache.
+  int rv = host_resolver->ResolveFromCache(resolve_info, &addresses, net_log);
+
+  DCHECK_NE(rv, ERR_IO_PENDING);
+  if (rv == OK && !addresses.empty()) {
+    // Checking only the first address should be sufficient.
+    IPEndPoint ip_end_point = addresses.front();
+    net::IPAddress ip_address = ip_end_point.address();
+    if (ip_address.IsReserved())
+      return true;
+  }
+
+  return false;
+}
+
+}  // namespace internal
+
+}  // namespace nqe
+
+}  // namespace net