telemetry: Remove command line args from page test

tools/perf/benchmarks/v8.py

Index: tools/perf/benchmarks/v8.py
diff --git a/tools/perf/benchmarks/v8.py b/tools/perf/benchmarks/v8.py
index 3b86416d1792e50b51d7c3e9a3f0c0f3b4cb682b..36004b561599a27e124aa8c56d44339691e7367d 100644
--- a/tools/perf/benchmarks/v8.py
+++ b/tools/perf/benchmarks/v8.py
@@ -10,11 +10,10 @@ from telemetry import benchmark
 @benchmark.Disabled  # crbug.com/416502
 class V8GarbageCollectionCases(benchmark.Benchmark):
   """Measure V8 metrics on the garbage collection cases."""
-  test = timeline_based_measurement.TimelineBasedMeasurement
-  page_set = page_sets.GarbageCollectionCasesPageSet
+  def CreatePageTest(self, options):
+    # TODO(ernstm): Remove v8-overhead when benchmark relevant v8 events become
+    # available in the 'benchmark' category.
+    return timeline_based_measurement.TimelineBasedMeasurement(
+        overhead_level='v8-overhead')
 
-  # TODO(ernstm): Remove this argument when benchmark relevant v8 events become
-  # available in the 'benchmark' category.
-  @classmethod
-  def SetArgumentDefaults(cls, parser):
-    parser.set_defaults(overhead_level='v8-overhead')
+  page_set = page_sets.GarbageCollectionCasesPageSet