Telemetry / Memory benchmark fix: Separate histograms for different tests.

tools/perf/perf_tools/memory_benchmark.py

Index: tools/perf/perf_tools/memory_benchmark.py
diff --git a/tools/perf/perf_tools/memory_benchmark.py b/tools/perf/perf_tools/memory_benchmark.py
index 27405734b3ba28f3a0526a2c1ab236139d32bf91..8e9471f5c5cf7361cd2f778f9c94d7e18cdca1ea 100644
--- a/tools/perf/perf_tools/memory_benchmark.py
+++ b/tools/perf/perf_tools/memory_benchmark.py
@@ -1,6 +1,7 @@
 # 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.
+from telemetry import histogram_measurement
 from telemetry import multi_page_benchmark
 
 MEMORY_HISTOGRAMS = [
@@ -15,6 +16,15 @@ BROWSER_MEMORY_HISTOGRAMS =  [
 class MemoryBenchmark(multi_page_benchmark.MultiPageBenchmark):
   def __init__(self):
     super(MemoryBenchmark, self).__init__('stress_memory')
+    self.histograms = (
+        [histogram_measurement.HistogramMeasurement(h)
+         for h in MEMORY_HISTOGRAMS] +
+        [histogram_measurement.HistogramMeasurement(h, True)
+         for h in BROWSER_MEMORY_HISTOGRAMS])
+
+  def WillNavigateToPage(self, page, tab):
+    for h in self.histograms:
+      h.Start(page, tab)
 
   def CustomizeBrowserOptions(self, options):
     options.AppendExtraBrowserArg('--dom-automation')
@@ -31,18 +41,5 @@ class MemoryBenchmark(multi_page_benchmark.MultiPageBenchmark):
     return hasattr(page, 'stress_memory')
 
   def MeasurePage(self, page, tab, results):
-    for histogram in MEMORY_HISTOGRAMS:
-      self._GetHistogramFromDomAutomation(tab, 'getHistogram', histogram,
-                                          results)
-    for histogram in BROWSER_MEMORY_HISTOGRAMS:
-      self._GetHistogramFromDomAutomation(tab, 'getBrowserHistogram', histogram,
-                                          results)
-
-  def _GetHistogramFromDomAutomation(self, tab, func, histogram, results):
-    name = histogram['name']
-    js = ('window.domAutomationController.%s ? '
-          'window.domAutomationController.%s("%s") : ""' % (func, func, name))
-    data = tab.EvaluateJavaScript(js)
-    if data:
-      results.Add(name.replace('.', '_'), histogram['units'], data,
-                  data_type='histogram')
+    for h in self.histograms:
+      h.GetValue(page, tab, results)