Use NESTABLE_ASYNC APIs to get NetLog data into Tracing

net/base/trace_net_log_observer.h

Index: net/base/trace_net_log_observer.h
diff --git a/net/base/trace_net_log_observer.h b/net/base/trace_net_log_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..31ffeddba2b7b32602605f0a762303e7ab2d5b91
--- /dev/null
+++ b/net/base/trace_net_log_observer.h
@@ -0,0 +1,50 @@
+// 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_TRACE_NET_LOG_OBSERVER_H_
+#define NET_BASE_TRACE_NET_LOG_OBSERVER_H_
+
+#include <stdio.h>

[mmenke, 2014/08/15 20:42:54]

not used.

[xunjieli, 2014/08/15 21:55:16]

Done. Sorry! I copied over another file. Should totally have checked this before
I uploaded the CL.

+
+#include "base/debug/trace_event_impl.h"
+#include "base/files/scoped_file.h"

[mmenke, 2014/08/15 20:42:54]

Not used.

[xunjieli, 2014/08/15 21:55:16]

Done.

+#include "net/base/net_log.h"
+
+namespace net {
+
+class NET_EXPORT TraceNetLogObserver : public NetLog::ThreadSafeObserver,

[mmenke, 2014/08/15 20:42:54]

Should include net/base/net_export.h

[xunjieli, 2014/08/15 21:55:16]

Done. I see! Thanks!

+     public base::debug::TraceLog::EnabledStateObserver {

[mmenke, 2014/08/15 20:42:54]

All parent classes should line up, so this should be:

class NET_EXPORT TraceNetLogObserver
    : public NetLog::ThreadSafeObserver,
      public base::debug::TraceLog::EnabledStateObserver {

[xunjieli, 2014/08/15 21:55:16]

Done. Thanks! I will keep that in mind next time.

+ public:
+  TraceNetLogObserver();
+  virtual ~TraceNetLogObserver();
+
+  void set_log_level(NetLog::LogLevel log_level);

[mmenke, 2014/08/15 20:42:54]

Only use this naming scheme when functions are inlined in the header.

[xunjieli, 2014/08/15 21:55:16]

Acknowledged. Also, I don't think we need the setter for now, so I will just
remove it.

+
+  void StartObserving(NetLog* net_log);
+
+  // Stops observing net_log().  Must already be watching.
+  void StopObserving();
+
+  // net::NetLog::ThreadSafeObserver implementation:
+  virtual void OnAddEntry(const NetLog::Entry& entry) OVERRIDE;
+
+  void WatchForTraceStart(NetLog* net_log);
+
+  void StopWatchForTraceStart();
+
+  // base::debug::TraceLog::EnabledStateChangedObserver overrides:

[mmenke, 2014/08/15 20:42:54]

nit:   overrides -> implementation, to be consistent with the similar line
above.

[xunjieli, 2014/08/15 21:55:16]

Done.

+  virtual void OnTraceLogEnabled() OVERRIDE;
+  virtual void OnTraceLogDisabled() OVERRIDE;
+ private:
+  // The LogLevel to log at.
+  NetLog::LogLevel log_level_;
+
+  NetLog* net_log_;
+
+  DISALLOW_COPY_AND_ASSIGN(TraceNetLogObserver);

[mmenke, 2014/08/15 20:42:54]

Should include base/macros.h for this and OVERRIDE

[xunjieli, 2014/08/15 21:55:16]

Partially done. How should I "OVERRIDE" on this?

[mmenke, 2014/08/15 21:59:15]

Sorry, I meant macros.h makes sure the "OVERRIDE" macro used on lines 30, 37,
and 38 is included, in addition to DISALLOW_COPY_AND_ASSIGN.  :)

[xunjieli, 2014/08/20 22:00:42]

I see. That makes sense. Thank you!
On 2014/08/15 21:59:15, mmenke wrote:

+};
+
+}  // namespace net
+
+#endif  // NET_BASE_TRACE_NET_LOG_OBSERVER_H_