Added support for improvement_direction to relevant values, which is propogated to chartjson.

tools/perf/metrics/power.py

Index: tools/perf/metrics/power.py
diff --git a/tools/perf/metrics/power.py b/tools/perf/metrics/power.py
index 0f33d2d41b19d751ae52f70c413578fe4e1c4798..bac20c8b93d54b7a2748545b65378b50324de2ab 100644
--- a/tools/perf/metrics/power.py
+++ b/tools/perf/metrics/power.py
@@ -6,6 +6,7 @@ import time
 
 from metrics import Metric
 from telemetry.core.platform import process_statistic_timeline_data
+from telemetry.value import improvement_direction
 from telemetry.value import scalar
 
 
@@ -112,12 +113,14 @@ class PowerMetric(Metric):
     if total_energy_consumption_mwh is not None:
       results.AddValue(scalar.ScalarValue(
           results.current_page, 'energy_consumption_mwh', 'mWh',
-          total_energy_consumption_mwh))
+          total_energy_consumption_mwh,
+          improvement_direction=improvement_direction.DOWN))
 
     if application_energy_consumption_mwh is not None:
       results.AddValue(scalar.ScalarValue(
           results.current_page, 'application_energy_consumption_mwh', 'mWh',
-          application_energy_consumption_mwh))
+          application_energy_consumption_mwh,
+          improvement_direction=improvement_direction.DOWN))
 
     component_utilization = self._results.get('component_utilization', {})
     # GPU Frequency.
@@ -126,14 +129,14 @@ class PowerMetric(Metric):
     if gpu_freq_hz is not None:
       results.AddValue(scalar.ScalarValue(
           results.current_page, 'gpu_average_frequency_hz', 'hz', gpu_freq_hz,
-          important=False))
+          important=False, improvement_direction=improvement_direction.DOWN))
 
     # Add idle wakeup numbers for all processes.
     for (process_type, stats) in self._results.get('cpu_stats', {}).items():
       trace_name_for_process = 'idle_wakeups_%s' % (process_type.lower())
       results.AddValue(scalar.ScalarValue(
           results.current_page, trace_name_for_process, 'count', stats,
-          important=False))
+          important=False, improvement_direction=improvement_direction.DOWN))
 
     # Add temperature measurements.
     whole_package_utilization = component_utilization.get('whole_package', {})
@@ -141,7 +144,8 @@ class PowerMetric(Metric):
     if board_temperature_c is not None:
       results.AddValue(scalar.ScalarValue(
           results.current_page, 'board_temperature', 'celsius',
-          board_temperature_c, important=False))
+          board_temperature_c, important=False,
+          improvement_direction=improvement_direction.DOWN))
 
     # Add CPU frequency measurements.
     frequency_hz = whole_package_utilization.get('frequency_percent')
@@ -151,7 +155,8 @@ class PowerMetric(Metric):
         frequency_sum += freq * (percent / 100.0)
       results.AddValue(scalar.ScalarValue(
           results.current_page, 'cpu_average_frequency_hz', 'Hz',
-          frequency_sum, important=False))
+          frequency_sum, important=False,
+          improvement_direction=improvement_direction.DOWN))
 
     # Add CPU c-state residency measurements.
     cstate_percent = whole_package_utilization.get('cstate_residency_percent')
@@ -159,7 +164,8 @@ class PowerMetric(Metric):
       for state, percent in cstate_percent.iteritems():
         results.AddValue(scalar.ScalarValue(
             results.current_page, 'cpu_cstate_%s_residency_percent' % state,
-            '%', percent, important=False))
+            '%', percent, important=False,
+            improvement_direction=improvement_direction.DOWN))
 
     self._results = None