[tools/perf] Refactor octane benchmark to use GetSystemTotalPhysicalMemory

tools/perf/benchmarks/octane.py

 # Copyright 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.
 
 """Runs Octane 2.0 javascript benchmark.
 
 Octane 2.0 is a modern benchmark that measures a JavaScript engine's performance
 by running a suite of tests representative of today's complex and demanding web
 applications. Octane's goal is to measure the performance of JavaScript code
 found in large, real-world web applications.
@@ skipping 62 matching lines @@
     super(_OctaneMeasurement, self).__init__()
     self._power_metric = None
 
   def CustomizeBrowserOptions(self, options):
     power.PowerMetric.CustomizeBrowserOptions(options)
 
   def WillStartBrowser(self, platform):
     self._power_metric = power.PowerMetric(platform)
 
   def WillNavigateToPage(self, page, tab):
-    memory_stats = tab.browser.memory_stats
-    if ('SystemTotalPhysicalMemory' in memory_stats and
-        memory_stats['SystemTotalPhysicalMemory'] < 1 * _GB):
+    total_memory = tab.browser.platform.GetSystemTotalPhysicalMemory()
+    if total_memory is not None and total_memory < 1 * _GB:

[nednguyen, 2016/09/02 16:15:52]

Actually what do we do with this variable?

[perezju, 2016/09/03 10:05:43]

That seems to be it. Just skip the "zlib" test in the octane benchmark if the
platform does not have enough memory.

A bit more context of why the check was added:
https://codereview.chromium.org/450873002

I can see some alternatives:
- Remove the check entirely, and see whether this breaks or not on some devices
- Check for IsSvelte instead?

[nednguyen, 2016/09/03 11:43:05]

I see. Let's just keep this as-is to unblock your cleanup. 

       skipBenchmarks = '"zlib"'
     else:
       skipBenchmarks = ''
     page.script_to_evaluate_on_commit = """
         var __results = [];
         var __real_log = window.console.log;
         window.console.log = function(msg) {
           __results.push(msg);
           __real_log.apply(this, [msg]);
         }
@@ skipping 49 matching lines @@
 
   def CreateStorySet(self, options):
     ps = story.StorySet(
         archive_data_file='../page_sets/data/octane.json',
         base_dir=os.path.dirname(os.path.abspath(__file__)),
         cloud_storage_bucket=story.PUBLIC_BUCKET)
     ps.AddStory(page_module.Page(
         'http://chromium.github.io/octane/index.html?auto=1',
         ps, ps.base_dir, make_javascript_deterministic=False))
     return ps