Cleanup of page_measurement_results object

tools/perf/benchmarks/dom_perf.py

Index: tools/perf/benchmarks/dom_perf.py
diff --git a/tools/perf/benchmarks/dom_perf.py b/tools/perf/benchmarks/dom_perf.py
index 56aa59b043064ed8746d7a051f07b8b326b72af0..1a466947fca51b832519be37841a305ecf715ba2 100644
--- a/tools/perf/benchmarks/dom_perf.py
+++ b/tools/perf/benchmarks/dom_perf.py
@@ -10,6 +10,7 @@ from telemetry import test
 from telemetry.core import util
 from telemetry.page import page_measurement
 from telemetry.page import page_set
+from telemetry.value import merge_values
 
 
 def _GeometricMean(values):
@@ -57,10 +58,11 @@ class _DomPerfMeasurement(page_measurement.PageMeasurement):
 
   def DidRunTest(self, browser, results):
     # Now give the geometric mean as the total for the combined runs.
-    scores = []
-    for result in results.page_results:
-      scores.append(result[SCORE_TRACE_NAME].output_value)
-    total = _GeometricMean(scores)
+    combined = merge_values.MergeLikeValuesFromDifferentPages(
+        results.all_page_specific_values,
+        group_by_name_suffix=True)
+    combined_score = [x for x in combined if x.name == SCORE_TRACE_NAME][0]
+    total = _GeometricMean(combined_score.values)
     results.AddSummary(SCORE_TRACE_NAME, SCORE_UNIT, total, 'Total')