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

tools/perf/benchmarks/start_with_url.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 startup
 import page_sets
 from telemetry import benchmark
 
 
 class _StartWithUrl(benchmark.Benchmark):
   page_set = page_sets.StartupPagesPageSet
   test = startup.StartWithUrl
 
+  @classmethod
+  def Name(cls):
+    return 'start_with_url.startup_pages'
+
   def CreatePageTest(self, options):
     is_cold = (self.tag == 'cold')
     return self.test(cold=is_cold)
 
 
 @benchmark.Enabled('has tabs')
 @benchmark.Disabled('chromeos', 'linux', 'mac', 'win')
 class StartWithUrlCold(_StartWithUrl):
   """Measure time to start Chrome cold with startup URLs"""
   tag = 'cold'
   options = {'pageset_repeat': 5}
 
+  @classmethod
+  def Name(cls):
+    return 'start_with_url.cold.startup_pages'
+
 
 @benchmark.Enabled('has tabs')
 @benchmark.Disabled('chromeos', 'linux', 'mac', 'win')
 class StartWithUrlWarm(_StartWithUrl):
   """Measure time to start Chrome warm with startup URLs"""
   tag = 'warm'
   options = {'pageset_repeat': 10}
+  @classmethod
+  def Name(cls):
+    return 'start_with_url.warm.startup_pages'
+