Update from https://crrev.com/305340

net/base/net_log_util.h

 // 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.
 
 #ifndef NET_BASE_NET_LOG_UTIL_H_
 #define NET_BASE_NET_LOG_UTIL_H_
 
+#include <set>
+
 #include "base/memory/scoped_ptr.h"
 #include "net/base/net_export.h"
+#include "net/base/net_log.h"
 
 namespace base {
 class DictionaryValue;
 class Value;
 }
 
 namespace net {
 
 class URLRequestContext;
 
 // A set of flags that can be OR'd together to request specific information
 // about the current state of the URLRequestContext.  See GetNetInfo, below.
 enum NetInfoSource {
 #define NET_INFO_SOURCE(label, string, value) NET_INFO_ ## label = value,
 #include "net/base/net_info_source_list.h"
 #undef NET_INFO_SOURCE
   NET_INFO_ALL_SOURCES = -1,
 };
 
 // Utility methods for creating NetLog dumps.
 
-// Create a dictionary containing legend for net/ constants.
+// Create a dictionary containing a legend for net/ constants.
 NET_EXPORT scoped_ptr<base::DictionaryValue> GetNetConstants();
 
 // Retrieves a dictionary containing information about the current state of
 // |context|.  |info_sources| is a set of NetInfoSources OR'd together,
 // indicating just what information is being requested.  Each NetInfoSource adds
 // one top-level entry to the returned dictionary.
+//
+// May only be called on |context|'s thread.
 NET_EXPORT scoped_ptr<base::DictionaryValue> GetNetInfo(
     URLRequestContext* context, int info_sources);
 
+// Takes in a set of contexts and a NetLog::Observer, and passes in
+// NetLog::Entries to the observer for certain NetLog::Sources with pending
+// events.  This allows requests that were ongoing when logging was started to
+// have an initial event that has some information.  This is particularly useful
+// for hung requests.  Note that these calls are not protected by the NetLog's
+// lock, so this should generally be invoked before the observer starts watching
+// the NetLog.
+//
+// All members of |contexts| must be using the same NetLog, and live on the
+// current thread.
+//
+// Currently only creates events for URLRequests.
+//
+// The reason for not returning a list of NetLog::Entries is that entries don't
+// own most of their data, so it's simplest just to pass them in to the observer
+// directly while their data is on the stack.
+NET_EXPORT void CreateNetLogEntriesForActiveObjects(
+    const std::set<URLRequestContext*>& contexts,
+    NetLog::ThreadSafeObserver* observer);
+
 }  // namespace net
 
 #endif  // NET_BASE_NET_LOG_UTIL_H_