Add WebView startup time benchmark

tools/perf/benchmarks/system_health.py

 # Copyright 2016 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.
 
 import re
 
 from core import perf_benchmark
 from telemetry import benchmark
 from telemetry.timeline import tracing_category_filter
 from telemetry.web_perf import timeline_based_measurement
@@ skipping 28 matching lines @@
 
 
 @benchmark.Disabled('all')  # crbug.com/613050
 class SystemHealthTop25(_SystemHealthBenchmark):
   page_set = page_sets.Top25PageSet
 
   @classmethod
   def Name(cls):
     return 'system_health.top25'
 
+
 @benchmark.Disabled('android')  # crbug.com/601953
 @benchmark.Disabled('all')  # crbug.com/613050
 class SystemHealthKeyMobileSites(_SystemHealthBenchmark):
   page_set = page_sets.KeyMobileSitesPageSet
 
   @classmethod
   def Name(cls):
     return 'system_health.key_mobile_sites'
 
 
@@ skipping 41 matching lines @@
 class MobileMemorySystemHealth(_MemorySystemHealthBenchmark):
   """Mobile Chrome Memory System Health Benchmark."""
   page_set = page_sets.MobileMemorySystemHealthStorySet
 
   @classmethod
   def ShouldDisable(cls, possible_browser):
     # http://crbug.com/612144 (reference on Nexus 5X).
     return possible_browser.platform.GetDeviceTypeName() == 'Desktop' or (
         possible_browser.browser_type == 'reference' and
         possible_browser.platform.GetDeviceTypeName() == 'Nexus 5X')
+
+@benchmark.Enabled('android-webview')
+class WebviewStartupSystemHealthBenchmark(perf_benchmark.PerfBenchmark):
+  """Webview startup time benchmark
+
+  Benchmark that measures how long WebView takes to start up
+  and load a blank page. Since thie metric only requires the trace
+  markers recorded in atrace, Chrome tracing is not enabled for this
+  benchmark.
+  """
+  page_set = page_sets.BlankPageSet
+
+  def CreateTimelineBasedMeasurementOptions(self):
+    options = timeline_based_measurement.Options()
+    options.SetTimelineBasedMetric('webviewStartupMetric')
+    options.config.enable_atrace_trace = True
+    options.config.enable_chrome_trace = False
+    options.config.atrace_config.app_name = 'org.chromium.webview_shell'
+    return options
+
+  @classmethod
+  def Name(cls):
+    return 'system_health.webview_startup'