[telemetry] Add a V8GCTimes measurement and benchmarks.

tools/telemetry/telemetry/web_perf/timeline_based_measurement.py

Index: tools/telemetry/telemetry/web_perf/timeline_based_measurement.py
diff --git a/tools/telemetry/telemetry/web_perf/timeline_based_measurement.py b/tools/telemetry/telemetry/web_perf/timeline_based_measurement.py
index 03a90ad239a26c3e7f10723add0b54810d25d582..1a3bd2fb3f43c1c2e5b780d8afe8e00bc8c306ac 100644
--- a/tools/telemetry/telemetry/web_perf/timeline_based_measurement.py
+++ b/tools/telemetry/telemetry/web_perf/timeline_based_measurement.py
@@ -10,7 +10,6 @@ from telemetry.page import page_test
 from telemetry.timeline import model as model_module
 from telemetry.value import trace
 from telemetry.web_perf import timeline_interaction_record as tir_module
-from telemetry.web_perf.metrics import fast_metric
 from telemetry.web_perf.metrics import responsiveness_metric
 from telemetry.web_perf.metrics import smoothness
 
@@ -19,13 +18,11 @@ from telemetry.web_perf.metrics import smoothness
 # overhead increases. The user of the measurement must therefore chose between
 # a few levels of instrumentation.
 NO_OVERHEAD_LEVEL = 'no-overhead'
-V8_OVERHEAD_LEVEL = 'v8-overhead'
 MINIMAL_OVERHEAD_LEVEL = 'minimal-overhead'
 DEBUG_OVERHEAD_LEVEL = 'debug-overhead'
 
 ALL_OVERHEAD_LEVELS = [
   NO_OVERHEAD_LEVEL,
-  V8_OVERHEAD_LEVEL,
   MINIMAL_OVERHEAD_LEVEL,
   DEBUG_OVERHEAD_LEVEL
 ]
@@ -36,8 +33,6 @@ class InvalidInteractions(Exception):
 
 
 def _GetMetricFromMetricType(metric_type):
-  if metric_type == tir_module.IS_FAST:
-    return fast_metric.FastMetric()
   if metric_type == tir_module.IS_SMOOTH:
     return smoothness.SmoothnessMetric()
   if metric_type == tir_module.IS_RESPONSIVE:
@@ -134,9 +129,8 @@ class Options(object):
     The user of the measurement chooses the overhead level that is appropriate,
     and the tracing is filtered accordingly.
 
-    overhead_level: one of NO_OVERHEAD_LEVEL, V8_OVERHEAD_LEVEL,
-        MINIMAL_OVERHEAD_LEVEL, or DEBUG_OVERHEAD_LEVEL.
-        The v8 overhead level is a temporary solution that may be removed.
+    overhead_level: one of NO_OVERHEAD_LEVEL, MINIMAL_OVERHEAD_LEVEL, or
+        DEBUG_OVERHEAD_LEVEL.
     """
     self._overhead_level = overhead_level
 
@@ -182,11 +176,6 @@ class TimelineBasedMeasurement(object):
     assert self._overhead_level in ALL_OVERHEAD_LEVELS
     if self._overhead_level == NO_OVERHEAD_LEVEL:
       category_filter = tracing_category_filter.CreateNoOverheadFilter()
-    # TODO(ernstm): Remove this overhead level when benchmark relevant v8 events
-    # become available in the 'benchmark' category.
-    elif self._overhead_level == V8_OVERHEAD_LEVEL:
-      category_filter = tracing_category_filter.CreateNoOverheadFilter()
-      category_filter.AddIncludedCategory('v8')
     elif self._overhead_level == MINIMAL_OVERHEAD_LEVEL:
       category_filter = tracing_category_filter.CreateMinimalOverheadFilter()
     else: