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 73 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': 10}

[hush (inactive), 2016/09/02 18:48:02]

does the blank page set only contain one blank page?

I feel that the repeat of 10 is too few though...

[mikecase (-- gone --), 2016/09/06 16:40:28]

Yes, only contains a blank page so the test is very fast. And I up'ed the
repeats to 20.

 
   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'
+

[hush (inactive), 2016/09/02 18:48:02]

nit: remove this blank line

[petrcermak, 2016/09/05 12:45:51]

No, don't remove it. There should be two blank lines between all top-level
definitions.

[mikecase (-- gone --), 2016/09/06 16:40:28]

Done

+
+@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'