Update NetLog to be thread safe.

chrome/browser/net/load_timing_observer.h

 // Copyright (c) 2010 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 CHROME_BROWSER_NET_LOAD_TIMING_OBSERVER_H_
 #define CHROME_BROWSER_NET_LOAD_TIMING_OBSERVER_H_
 #pragma once
 
 #include "base/gtest_prod_util.h"
 #include "base/hash_tables.h"
@@ skipping 25 matching lines @@
   };
 
   struct SocketRecord {
     base::TimeTicks ssl_start;
     base::TimeTicks ssl_end;
   };
 
   LoadTimingObserver();
   ~LoadTimingObserver();
 
-  URLRequestRecord* GetURLRequestRecord(uint32 source_id);
-
   // Observer implementation:
   virtual void OnAddEntry(net::NetLog::EventType type,
                           const base::TimeTicks& time,
                           const net::NetLog::Source& source,
                           net::NetLog::EventPhase phase,
                           net::NetLog::EventParameters* params);
 
   static void PopulateTimingInfo(URLRequest* request,
                                  ResourceResponse* response);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(LoadTimingObserverTest,
                            ConnectJobRecord);
   FRIEND_TEST_ALL_PREFIXES(LoadTimingObserverTest,
                            SocketRecord);
 
+  // Note that |lock_| must be acquired before calling all of the following
+  // functions.
   void OnAddURLRequestEntry(net::NetLog::EventType type,
                             const base::TimeTicks& time,
                             const net::NetLog::Source& source,
                             net::NetLog::EventPhase phase,
                             net::NetLog::EventParameters* params);
 
   void OnAddConnectJobEntry(net::NetLog::EventType type,
                             const base::TimeTicks& time,
                             const net::NetLog::Source& source,
                             net::NetLog::EventPhase phase,
                             net::NetLog::EventParameters* params);
 
   void OnAddSocketEntry(net::NetLog::EventType type,
                         const base::TimeTicks& time,
                         const net::NetLog::Source& source,
                         net::NetLog::EventPhase phase,
                         net::NetLog::EventParameters* params);
 
-  URLRequestRecord* CreateURLRequestRecord(uint32 source_id);
-  void DeleteURLRequestRecord(uint32 source_id);
+  // |lock_| must be aquired for as long as the returned |URLRequestRecord*|
+  // is in use.
+  URLRequestRecord* GetURLRequestRecord(uint32 source_id);
+
+  Lock lock_;
 
   typedef base::hash_map<uint32, URLRequestRecord> URLRequestToRecordMap;
   typedef base::hash_map<uint32, ConnectJobRecord> ConnectJobToRecordMap;
   typedef base::hash_map<uint32, SocketRecord> SocketToRecordMap;
   URLRequestToRecordMap url_request_to_record_;
   ConnectJobToRecordMap connect_job_to_record_;
   SocketToRecordMap socket_to_record_;
   uint32 last_connect_job_id_;
   ConnectJobRecord last_connect_job_record_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadTimingObserver);
 };
 
 #endif  // CHROME_BROWSER_NET_LOAD_TIMING_OBSERVER_H_