Telemetry: Implement idle wakeups counting on Android.

tools/telemetry/telemetry/core/platform/__init__.py

Index: tools/telemetry/telemetry/core/platform/__init__.py
diff --git a/tools/telemetry/telemetry/core/platform/__init__.py b/tools/telemetry/telemetry/core/platform/__init__.py
index e11d51f99e8572479057a82ad51606cf4e27ee59..848936db6b3f81f0d35fd301f52cd71a696085f0 100644
--- a/tools/telemetry/telemetry/core/platform/__init__.py
+++ b/tools/telemetry/telemetry/core/platform/__init__.py
@@ -263,13 +263,18 @@ class Platform(object):
     """
     return self._platform_backend.CanMonitorPower()
 
+  def CanMeasureIdleWakeUps(self):
+    """Returns True iff idle wakeups can be monitored via
+    StartMeasuringIdleWakeUps() and StopMeasuringIdleWakeUps().
+    """
+    return self._platform_backend.CanMeasureIdleWakeUps()
+
   def CanMeasurePerApplicationPower(self):
     """Returns True if the power monitor can measure power for the target
     application in isolation. False if power measurement is for full system
     energy consumption."""
     return self._platform_backend.CanMeasurePerApplicationPower()
 
-
   def StartMonitoringPower(self, browser):
     """Starts monitoring power utilization statistics.
 
@@ -322,3 +327,13 @@ class Platform(object):
       }
     """
     return self._platform_backend.StopMonitoringPower()
+
+  def StartMeasuringIdleWakeUps(self):

[tonyg, 2014/11/14 21:34:03]

The platform API needs to report idle wakeups to the rest of telemetry in a
consistent way regardless of platform. We shouldn't do this scheme where they're
included in cpu stats on mac and here on other platforms. The whole point of the
platform API is to conceal these sorts of details.

Beyond consistency, I don't have super strong opinions about which way to go.
But idle wakeups sure does feel like a cpu stat.

+    """Starts monitoring idle wakeups."""
+    assert self._platform_backend.CanMeasureIdleWakeUps()
+    self._platform_backend.StartMeasuringIdleWakeUps()
+
+  def StopMeasuringIdleWakeUps(self):
+    """Stops monitoring idle wakeups."""
+    assert self._platform_backend.CanMeasureIdleWakeUps()
+    self._platform_backend.StopMeasuringIdleWakeUps()