Add WebView Multiprocess startup 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 chrome_trace_category_filter
 from telemetry.web_perf import timeline_based_measurement
@@ skipping 133 matching lines @@
 
 @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
+  options = {'pageset_repeat': 20}
+
+  def CreateStorySet(self, options):
+    return page_sets.SystemHealthStorySet(platform='mobile', case='blank')
 
   def CreateTimelineBasedMeasurementOptions(self):
     options = timeline_based_measurement.Options()
     options.SetTimelineBasedMetrics(['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 ShouldTearDownStateAfterEachStoryRun(cls):
     return True
 
   @classmethod
   def Name(cls):
     return 'system_health.webview_startup'
+
+
+@benchmark.Enabled('android-webview')
+class WebviewMultiprocessStartupSystemHealthBenchmark(
+    WebviewStartupSystemHealthBenchmark):
+  """Webview multiprocess startup time benchmark
+
+  Benchmark that measures how long WebView takes to start up
+  and load a blank page with multiprocess enabled.
+  """
+
+  def SetExtraBrowserOptions(self, options):
+    options.AppendExtraBrowserArgs(
+        ['--webview-sandboxed-renderer'])
+
+  @classmethod
+  def Name(cls):
+    return 'system_health.webview_startup_multiprocess'