[Telemetry] Measure power in tab_switching measurement

tools/telemetry/telemetry/core/platform/platform_backend.py

Index: tools/telemetry/telemetry/core/platform/platform_backend.py
diff --git a/tools/telemetry/telemetry/core/platform/platform_backend.py b/tools/telemetry/telemetry/core/platform/platform_backend.py
index 74bbf8b4c04844e4678118da1a6cca4969cbfdf1..83827e1c72f8419167ab6a4ea4544f42e8b7611c 100644
--- a/tools/telemetry/telemetry/core/platform/platform_backend.py
+++ b/tools/telemetry/telemetry/core/platform/platform_backend.py
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import time
-
 # pylint: disable=W0613
 
 
@@ -116,14 +114,6 @@ class PlatformBackend(object):
   def StopVideoCapture(self):
     raise NotImplementedError()
 
-  def CanMonitorPowerSync(self):
-    return self.CanMonitorPowerAsync()
-
-  def MonitorPowerSync(self, duration_ms):
-    self.StartMonitoringPowerAsync()
-    time.sleep(duration_ms / 1000.)
-    return self.StopMonitoringPowerAsync()
-
   def CanMonitorPowerAsync(self):
     return False