cc: Fixed computation of dropped frames.

tools/perf/metrics/smoothness.py

 # Copyright 2013 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.
 import os
 
 from telemetry.core import util
 
 TIMELINE_MARKER = 'smoothness_scroll'
 
 class SmoothnessMetrics(object):
@@ skipping 96 matching lines @@
 
   results.Add('first_paint', 'ms', round(first_paint_secs * 1000, 1))
 
 def CalcResults(benchmark_stats, results):
   s = benchmark_stats
 
   # Scroll Results
   results.Add('mean_frame_time', 'ms',
               Average(s.total_time, s.screen_frame_count, 1000, 3))
   results.Add('dropped_percent', '%',
-              Average(s.dropped_frame_count, s.screen_frame_count,
-                      100, 1),
+              Average(s.dropped_frame_count,
+                      s.screen_frame_count + s.dropped_frame_count, 100, 1),
               data_type='unimportant')
   results.Add('percent_impl_scrolled', '%',
               Average(s.impl_thread_scroll_count,
                       s.impl_thread_scroll_count +
                       s.main_thread_scroll_count,
                       100, 1),
               data_type='unimportant')
   results.Add('average_num_layers_drawn', '',
               Average(s.drawn_layer_count, s.screen_frame_count, 1, 1),
               data_type='unimportant')
@@ skipping 46 matching lines @@
               Average(s.touch_ui_latency, s.touch_ui_count, 1000, 3),
               data_type='unimportant')
   results.Add('average_touch_acked_latency', 'ms',
               Average(s.touch_acked_latency, s.touch_acked_count,
                       1000, 3),
               data_type='unimportant')
   results.Add('average_scroll_update_latency', 'ms',
               Average(s.scroll_update_latency, s.scroll_update_count,
                       1000, 3),
               data_type='unimportant')