Add WebView startup time benchmark

tools/perf/benchmarks/system_health.py

Index: tools/perf/benchmarks/system_health.py
diff --git a/tools/perf/benchmarks/system_health.py b/tools/perf/benchmarks/system_health.py
index 8037c349c72a354688d53825fff3b0c6ed999d76..dfbf16c5b430bbe5924b3301c9eac345c0ffffe0 100644
--- a/tools/perf/benchmarks/system_health.py
+++ b/tools/perf/benchmarks/system_health.py
@@ -46,6 +46,7 @@ class SystemHealthTop25(_SystemHealthBenchmark):
   def Name(cls):
     return 'system_health.top25'
 
+
 @benchmark.Disabled('android')  # crbug.com/601953
 @benchmark.Disabled('all')  # crbug.com/613050
 class SystemHealthKeyMobileSites(_SystemHealthBenchmark):
@@ -88,6 +89,30 @@ class _MemorySystemHealthBenchmark(perf_benchmark.PerfBenchmark):
     return not _IGNORED_STATS_RE.search(value.name)
 
 
+@benchmark.Enabled('android')

[Zhen Wang, 2016/06/09 00:35:08]

I am almost sure you will need @benchmark.Enabled('android-webview').

I will stamp once perezju confirms.

[perezju, 2016/06/09 10:51:06]

Yes, this should be android-webview.

[alexandermont, 2016/06/09 16:26:19]

Done

+class WebviewStartupSystemHealthBenchmark(_SystemHealthBenchmark):

[perezju, 2016/06/09 10:51:07]

I don't think this should subclass _SystemHealthBenchmark, can you subclass
directly perf_benchmark.PerfBenchmark instead?

[petrcermak, 2016/06/09 12:56:03]

This class is now wedged in the middle of memory system health bemchmarks:

class _MemorySystemHealthBenchmark
*** class WebviewStartupSystemHealthBenchmark ***
class DesktopMemorySystemHealthBenchmark
class MobileMemorySystemHealthBenchmark

Could you please move it either before, or after the memory block? Thanks!

[alexandermont, 2016/06/09 16:26:19]

Done

+  """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

[perezju, 2016/06/09 11:02:51]

+torne, do we also want to run the benchmark on some other pages?

[Torne, 2016/06/09 11:22:31]

I don't think it's particularly important right now. A blank page captures the
main thing we care about.

+
+  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'
+
+
 class DesktopMemorySystemHealth(_MemorySystemHealthBenchmark):
   """Desktop Chrome Memory System Health Benchmark."""
   page_set = page_sets.DesktopMemorySystemHealthStorySet