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

tools/telemetry/telemetry/web_perf/metrics/smoothness.py

Index: tools/telemetry/telemetry/web_perf/metrics/smoothness.py
diff --git a/tools/telemetry/telemetry/web_perf/metrics/smoothness.py b/tools/telemetry/telemetry/web_perf/metrics/smoothness.py
index f63fea8bed3b45ec5c6ceaab2248f226f85c7e76..00eb74fe3043e4df4af057e98334b3c4489d3fa3 100644
--- a/tools/telemetry/telemetry/web_perf/metrics/smoothness.py
+++ b/tools/telemetry/telemetry/web_perf/metrics/smoothness.py
@@ -5,6 +5,7 @@
 import logging
 from telemetry.perf_tests_helper import FlattenList
 from telemetry.util import statistics
+from telemetry.value import improvement_direction
 from telemetry.value import list_of_scalar_values
 from telemetry.value import scalar
 from telemetry.web_perf.metrics import rendering_stats
@@ -124,22 +125,26 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
             page, 'avg_surface_fps', 'fps', avg_surface_fps,
             description='Average frames per second as measured by the '
                         'platform\'s SurfaceFlinger.',
-            none_value_reason=none_value_reason),
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.UP),
         scalar.ScalarValue(
             page, 'jank_count', 'janks', jank_count,
             description='Number of changes in frame rate as measured by the '
                         'platform\'s SurfaceFlinger.',
-            none_value_reason=none_value_reason),
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN),
         scalar.ScalarValue(
             page, 'max_frame_delay', 'vsyncs', max_frame_delay,
             description='Largest frame time as measured by the platform\'s '
                         'SurfaceFlinger.',
-            none_value_reason=none_value_reason),
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN),
         list_of_scalar_values.ListOfScalarValues(
             page, 'frame_lengths', 'vsyncs', frame_lengths,
             description='Frame time in vsyncs as measured by the platform\'s '
                         'SurfaceFlinger.',
-            none_value_reason=none_value_reason)
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN)
     )
 
   def _ComputeLatencyMetric(self, page, stats, name, list_of_latency_lists):
@@ -160,11 +165,13 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
       scalar.ScalarValue(
           page, 'mean_%s' % name, 'ms', mean_latency,
           description='Arithmetic mean of the raw %s values' % name,
-          none_value_reason=none_value_reason),
+          none_value_reason=none_value_reason,
+          improvement_direction=improvement_direction.DOWN),
       scalar.ScalarValue(
           page, '%s_discrepancy' % name, 'ms', latency_discrepancy,
           description='Discrepancy of the raw %s values' % name,
-          none_value_reason=none_value_reason)
+          none_value_reason=none_value_reason,
+          improvement_direction=improvement_direction.DOWN)
     )
 
   def _ComputeFirstGestureScrollUpdateLatency(self, page, stats):
@@ -186,7 +193,8 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
                     'takes to process the very first gesture scroll update '
                     'input event. The first scroll gesture can often get '
                     'delayed by work related to page loading.',
-        none_value_reason=none_value_reason),
+        none_value_reason=none_value_reason,
+        improvement_direction=improvement_direction.DOWN),
     )
 
   def _ComputeQueueingDuration(self, page, stats):
@@ -210,7 +218,8 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
                     'ScheduledActionSendBeginMainFrame event in the compositor '
                     'thread and the corresponding BeginMainFrame event in the '
                     'main thread.',
-        none_value_reason=none_value_reason)
+        none_value_reason=none_value_reason,
+        improvement_direction=improvement_direction.DOWN)
 
   def _ComputeFrameTimeMetric(self, page, stats):
     """Returns Values for the frame time metrics.
@@ -236,15 +245,18 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
             page, 'frame_times', 'ms', frame_times,
             description='List of raw frame times, helpful to understand the '
                         'other metrics.',
-            none_value_reason=none_value_reason),
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN),
         scalar.ScalarValue(
             page, 'mean_frame_time', 'ms', mean_frame_time,
             description='Arithmetic mean of frame times.',
-            none_value_reason=none_value_reason),
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN),
         scalar.ScalarValue(
             page, 'percentage_smooth', 'score', percentage_smooth,
             description='Percentage of frames that were hitting 60 fps.',
-            none_value_reason=none_value_reason)
+            none_value_reason=none_value_reason,
+            improvement_direction=improvement_direction.DOWN)
     )
 
   def _ComputeFrameTimeDiscrepancy(self, page, stats):
@@ -267,7 +279,8 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
                     'is important because even if the mean and 95th '
                     'percentile are good, one long pause in the middle of an '
                     'interaction is still bad.',
-        none_value_reason=none_value_reason)
+        none_value_reason=none_value_reason,
+        improvement_direction=improvement_direction.DOWN)
 
   def _ComputeMeanPixelsApproximated(self, page, stats):
     """Add the mean percentage of pixels approximated.
@@ -285,4 +298,5 @@ class SmoothnessMetric(timeline_based_metric.TimelineBasedMetric):
         page, 'mean_pixels_approximated', 'percent', mean_pixels_approximated,
         description='Percentage of pixels that were approximated '
                     '(checkerboarding, low-resolution tiles, etc.).',
-        none_value_reason=none_value_reason)
+        none_value_reason=none_value_reason,
+        improvement_direction=improvement_direction.DOWN)