Add key_idle_power_cases for ensuring idle activity on Android

tools/perf/benchmarks/thread_times.py

 # 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.
 
 from telemetry import benchmark
 
 from benchmarks import silk_flags
 from measurements import thread_times
 import page_sets
 
@@ skipping 76 matching lines @@
 
 @benchmark.Enabled('android')
 class ThreadTimesPolymer(_ThreadTimes):
   """Measures timeline metrics while performing smoothness action on
   Polymer cases."""
   page_set = page_sets.PolymerPageSet
   @classmethod
   def Name(cls):
     return 'thread_times.polymer'
 
+@benchmark.Enabled('android')
+class ThreadTimesKeyIdlePowerCases(_ThreadTimes):
+  """Measures timeline metrics for sites that should be idle in foreground
+  and background scenarios. The metrics are per-second rather than per-frame."""
+  page_set = page_sets.KeyIdlePowerCasesPageSet
+
+  @classmethod
+  def Name(cls):
+    return 'thread_times.key_idle_power_cases'
+
+  @classmethod
+  def ValueCanBeAddedPredicate(cls, value, _):
+    # Only report per-second metrics.
+    return 'per_frame' not in value.name and 'mean_frame' not in value.name