[Telemetry] Rename translate_common_values + add none_value/description support

telemetry/telemetry/web_perf/timeline_based_measurement.py

Index: telemetry/telemetry/web_perf/timeline_based_measurement.py
diff --git a/telemetry/telemetry/web_perf/timeline_based_measurement.py b/telemetry/telemetry/web_perf/timeline_based_measurement.py
index ff3fd142f1a384d1bab5b3658b16966aabf7d73f..ce246e45409b8cd5d19e86ba4c1188129938f015 100644
--- a/telemetry/telemetry/web_perf/timeline_based_measurement.py
+++ b/telemetry/telemetry/web_perf/timeline_based_measurement.py
@@ -11,7 +11,7 @@ from telemetry.timeline import model as model_module
 from telemetry.timeline import tracing_category_filter
 from telemetry.timeline import tracing_config
 from telemetry.value import trace
-from telemetry.value import translate_common_values
+from telemetry.value import common_value_helpers
 from telemetry.web_perf.metrics import timeline_based_metric
 from telemetry.web_perf.metrics import blob_timeline
 from telemetry.web_perf.metrics import jitter_timeline
@@ -305,13 +305,13 @@ class TimelineBasedMeasurement(story_test.StoryTest):
     failure_dicts = mre_result.failures
     for d in failure_dicts:
       results.AddValue(
-          translate_common_values.TranslateMreFailure(d, page))
+          common_value_helpers.TranslateMreFailure(d, page))
 
     value_dicts = mre_result.pairs.get('values', [])
     for d in value_dicts:
-      if translate_common_values.IsScalarNumericValue(d):
+      if common_value_helpers.IsScalarNumericValue(d):
         results.AddValue(
-            translate_common_values.TranslateScalarValue(d, page))
+            common_value_helpers.TranslateScalarValue(d, page))
 
   def _ComputeLegacyTimelineBasedMetrics(self, results, trace_result):
     model = model_module.TimelineModel(trace_result)