Telemetry on android: improves RawDisplayFrameRateMeasurement.

tools/telemetry/telemetry/page/scrolling_action.py

 # Copyright (c) 2012 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 os
 
 from telemetry.core import util
 from telemetry.page import page_action
 
 class ScrollingAction(page_action.PageAction):
   def __init__(self, attributes=None):
     super(ScrollingAction, self).__init__(attributes)
 
   def WillRunAction(self, page, tab):
     with open(
       os.path.join(os.path.dirname(__file__),
                    'scrolling_action.js')) as f:
       js = f.read()
       tab.ExecuteJavaScript(js)
 
     tab.ExecuteJavaScript("""
         window.__scrollingActionDone = false;
         window.__scrollingAction = new __ScrollingAction(function() {
           window.__scrollingActionDone = true;
         });
      """)
 
   def RunAction(self, page, tab, previous_action):
-    try:
-      if tab.browser.platform.IsRawDisplayFrameRateSupported():
-        tab.browser.platform.StartRawDisplayFrameRateMeasurement('')
-      # scrollable_element_function is a function that passes the scrollable
-      # element on the page to a callback. For example:
-      #   function (callback) {
-      #     callback(document.getElementById('foo'));
-      #   }
-      if hasattr(self, 'scrollable_element_function'):
-        tab.ExecuteJavaScript("""
-            (%s)(function(element) {
-              window.__scrollingAction.start(element);
-            });""" % (self.scrollable_element_function))
-      else:
-        tab.ExecuteJavaScript(
-          'window.__scrollingAction.start(document.body);')
+    # scrollable_element_function is a function that passes the scrollable
+    # element on the page to a callback. For example:
+    #   function (callback) {
+    #     callback(document.getElementById('foo'));
+    #   }
+    if hasattr(self, 'scrollable_element_function'):
+      tab.ExecuteJavaScript("""
+          (%s)(function(element) {
+            window.__scrollingAction.start(element);
+          });""" % (self.scrollable_element_function))
+    else:
+      tab.ExecuteJavaScript(
+        'window.__scrollingAction.start(document.body);')
 
-      # Poll for scroll benchmark completion.
-      util.WaitFor(lambda: tab.EvaluateJavaScript(
-          'window.__scrollingActionDone'), 60)
-    finally:
-      if tab.browser.platform.IsRawDisplayFrameRateSupported():
-        tab.browser.platform.StopRawDisplayFrameRateMeasurement()
+    # Poll for scroll benchmark completion.
+    util.WaitFor(lambda: tab.EvaluateJavaScript(
+        'window.__scrollingActionDone'), 60)
 
   def CanBeBound(self):
     return True
 
   def BindMeasurementJavaScript(self, tab, start_js, stop_js):
     # Make the scrolling action start and stop measurement automatically.
     tab.ExecuteJavaScript("""
         window.__scrollingAction.beginMeasuringHook = function() { %s };
         window.__scrollingAction.endMeasuringHook = function() { %s };
     """ % (start_js, stop_js))