[Telemetry] Close msr server win after checking whether platform can monitor power.

tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py

Index: tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py
diff --git a/tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py b/tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py
index 74dac5ca041dded858e875130e6d0763319b1222..d9ffe20c400e44f0b1af87b377441cf64c5f094b 100644
--- a/tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py
+++ b/tools/telemetry/telemetry/internal/platform/power_monitor/msr_power_monitor.py
@@ -133,7 +133,12 @@ class MsrPowerMonitorWin(MsrPowerMonitor):
       logging.info('Cannot monitor power: pre-Sandy Bridge CPU.')
       return False
 
-    return self._CheckMSRs()
+    msr_return_value = self._CheckMSRs()
+    # Since _CheckMSRs() start the MSR server, we must close it after checking

[dtu, 2015/11/09 18:13:24]

nit: starts

[nednguyen, 2015/11/09 18:16:44]

Done.

+    # to avoid leaking msr server process.
+    self._backend.CloseMsrServer()

[dtu, 2015/11/09 18:13:25]

We need to do so on both Linux and Win, so perhaps it's better inside
_CheckMSRs().

[nednguyen, 2015/11/09 18:16:44]

CloseMsrServer is win_platform_backend only, updated the comment to reflect
this.

[dtu, 2015/11/09 18:25:46]

Ah, yes, your'e right.

+    return msr_return_value
+
 
   def StopMonitoringPower(self):
     power_statistics = super(MsrPowerMonitorWin, self).StopMonitoringPower()