[Telemetry] Explicitly define Name() method for all perf benchmarks

tools/perf/benchmarks/polymer_load.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from measurements import polymer_load
 import page_sets
 from telemetry import benchmark
 
 
 @benchmark.Enabled('android')
 class PolymerLoadPica(benchmark.Benchmark):
   """Measures time to polymer-ready for Pica (News Reader)."""
   test = polymer_load.PolymerLoadMeasurement
   page_set = page_sets.PicaPageSet
 
+  @classmethod
+  def Name(cls):
+    return 'polymer_load.pica'
+
 
 # There is something weird about this test (or a test that precedes it)
 # that causes it to fail in telemetry_perf_unittests when it is not run
 # as the first of the benchmark_smoke_unittest test cases.
 # See crbug.com/428207.
 #@benchmark.Enabled('android')
 @benchmark.Disabled
 class PolymerLoadTopeka(benchmark.Benchmark):
   """Measures time to polymer-ready for Topeka (Quiz App)."""
   test = polymer_load.PolymerLoadMeasurement
   page_set = page_sets.TopekaPageSet
+  @classmethod
+  def Name(cls):
+    return 'polymer_load.topeka'
+