[Telemetry perf] Only track mean_pixels_approximated & mean_pixels_checkerboarded for smoothness.tough_scrolling_cases

[PERF SHERRIF] This may cause alert of dashboard stops outputting
these metrics but they are intentional.

BUG=529331

Review URL: https://codereview.chromium.org/1415763002

Cr-Commit-Position: refs/heads/master@{#354938}

1 files changed, 10 insertions, 1 deletions

diff --git a/tools/perf/benchmarks/smoothness.py b/tools/perf/benchmarks/smoothness.py
index 2e88fc5..f11dd7e 100644
--- a/tools/perf/benchmarks/smoothness.py
+++ b/tools/perf/benchmarks/smoothness.py
@@ -27,7 +27,8 @@ class _Smoothness(perf_benchmark.PerfBenchmark):
     return 'smoothness'
 
   @classmethod
-  def ValueCanBeAddedPredicate(cls, value, _):
+  def ValueCanBeAddedPredicate(cls, value, is_first_result):
+    del is_first_result  # unused
     if (value.name == 'first_gesture_scroll_update_latency' and
         value.page.url in cls._PAGES_WITHOUT_SCROLL_GESTURE_BLACKLIST and
         value.values is None):
@@ -327,6 +328,14 @@ class SmoothnessToughScrollingCases(_Smoothness):
   page_set = page_sets.ToughScrollingCasesPageSet
 
   @classmethod
+  def ValueCanBeAddedPredicate(cls, value, is_first_result):
+    del is_first_result  # unused
+    # Only keep 'mean_pixels_approximated' and 'mean_pixels_checkerboarded'
+    # metrics. (crbug.com/529331)
+    return value.name in ('mean_pixels_approximated',
+                          'mean_pixels_checkerboarded')
+
+  @classmethod
   def Name(cls):
     return 'smoothness.tough_scrolling_cases'