telemetry: Add 'webkit' category back to smoothness benchmark.

tools/perf/measurements/smoothness.py

 # Copyright (c) 2013 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 metrics import loading
 from metrics import smoothness
 from metrics.gpu_rendering_stats import GpuRenderingStats
 from telemetry.page import page_measurement
 
 
 class DidNotScrollException(page_measurement.MeasurementFailure):
@@ skipping 26 matching lines @@
 
   def CustomizeBrowserOptions(self, options):
     smoothness.SmoothnessMetrics.CustomizeBrowserOptions(options)
     if self.force_enable_threaded_compositing:
       options.AppendExtraBrowserArgs('--enable-threaded-compositing')
 
   def CanRunForPage(self, page):
     return hasattr(page, 'smoothness')
 
   def WillRunAction(self, page, tab, action):
-    tab.browser.StartTracing('webkit.console,benchmark', 60)
+    # TODO(ermst): Remove "webkit" category after Blink r157377 is picked up by
+    # the reference builds.
+    tab.browser.StartTracing('webkit,webkit.console,benchmark', 60)
     if tab.browser.platform.IsRawDisplayFrameRateSupported():
       tab.browser.platform.StartRawDisplayFrameRateMeasurement()
     self._metrics = smoothness.SmoothnessMetrics(tab)
     if action.CanBeBound():
       self._metrics.BindToAction(action)
     else:
       self._metrics.Start()
 
   def DidRunAction(self, page, tab, action):
     if tab.browser.platform.IsRawDisplayFrameRateSupported():
@@ skipping 30 matching lines @@
 
     if self.options.report_all_results:
       for k, v in rendering_stats_deltas.iteritems():
         results.Add(k, '', v)
 
     if tab.browser.platform.IsRawDisplayFrameRateSupported():
       for r in tab.browser.platform.GetRawDisplayFrameRateMeasurements():
         if r.value is None:
           raise MissingDisplayFrameRate(r.name)
         results.Add(r.name, r.unit, r.value)