[Chromoting] Use ProcessStatsSender in DesktopSessionAgent (desktop process)

remoting/host/chromoting_messages.h

Index: remoting/host/chromoting_messages.h
diff --git a/remoting/host/chromoting_messages.h b/remoting/host/chromoting_messages.h
index 51a9d7056e4a1284dd77de2cb9d8c83891007f28..f0d455eb7ec0c7cb6a4b7328754c9e0fda1865bf 100644
--- a/remoting/host/chromoting_messages.h
+++ b/remoting/host/chromoting_messages.h
@@ -13,6 +13,7 @@
 #include "remoting/host/chromoting_param_traits.h"
 #include "remoting/host/desktop_environment_options.h"
 #include "remoting/host/screen_resolution.h"
+#include "remoting/proto/process_stats.pb.h"
 #include "remoting/protocol/errors.h"
 #include "remoting/protocol/transport.h"
 #include "third_party/webrtc/modules/desktop_capture/desktop_capturer.h"
@@ -265,3 +266,11 @@ IPC_MESSAGE_CONTROL0(ChromotingNetworkToRemoteSecurityKeyMsg_ConnectionReady)
 // Error indicating the request originated from outside the remoted session.
 // The IPC channel will be disconnected after this message has been sent.
 IPC_MESSAGE_CONTROL0(ChromotingNetworkToRemoteSecurityKeyMsg_InvalidSession)
+
+// Starts to report process resource usage.

[joedow, 2017/06/13 20:12:11]

Do you need a message to stop sending process stats?  The lifetime of the P2P
channel is not necessarily tied to the duration of the session so if a client
kills the P2P channel, do you intend to keep sending stats to the network
process?

[Hzj_jie, 2017/06/14 23:12:23]

Done.

+IPC_MESSAGE_CONTROL1(ChromotingNetworkMsg_StartProcessStatsReport,

[joedow, 2017/06/13 20:12:12]

Other messages use a ProductNameSendNameReceiverNameMsg_MessageType format, are
you intending to pass the same message to all processes?  If so, it would be
good to update the name to show that: e.g.
ChromotingNetworkAnyMsg_StartProcessStatsReport

[Hzj_jie, 2017/06/14 23:12:23]

I have not seen an "Any" in this file. Yes, this message is expected to be sent
from network process to both daemon and desktop processes. Updated.

+                     int32_t /* interval_ms */)

[joedow, 2017/06/13 20:12:12]

Can the interval be compiled into the sender (so they all have the same
interval) or is there a benefit to passing it in the IPC message?

[Hzj_jie, 2017/06/14 23:12:23]

It benefits the tests. But it's also reasonable to control it by network process
just in case we have a shorter interval for experiments, but a longer interval
to detect any unexpected error.

[joedow, 2017/06/15 22:50:44]

I'm not sure that we will need to change it but I don't feel too passionate
about it.  If you do decide this is mostly for testing, just add a
SetIntervalForTest() to the classes which need it an then clean this up.

[Hzj_jie, 2017/06/16 00:39:28]

If you do not have a strong opinion, I would keep it as-is. It benefits both
tests and future user-cases.

+
+// Reports process resource usage to network process.
+IPC_MESSAGE_CONTROL1(ChromotingNetworkMsg_ReportProcessStats,
+                     remoting::protocol::AggregatedProcessResourceUsage)