Kill --memory-metrics and on-demand Memory.Browser/RenderUsed histograms

tools/perf/measurements/memory_multi_tab.py

Index: tools/perf/measurements/memory_multi_tab.py
diff --git a/tools/perf/measurements/memory_multi_tab.py b/tools/perf/measurements/memory_multi_tab.py
index de307a8781868dabeb6d534f6de99edf04ff289c..62f6883dd4721db68328d88b1eaa84b0b837464e 100644
--- a/tools/perf/measurements/memory_multi_tab.py
+++ b/tools/perf/measurements/memory_multi_tab.py
@@ -24,12 +24,6 @@ class MemoryMultiTab(page_test.PageTest):
   def DidStartBrowser(self, browser):
     self._memory_metric = memory.MemoryMetric(browser)
 
-  def CustomizeBrowserOptions(self, options):
-    memory.MemoryMetric.CustomizeBrowserOptions(options)
-    # Since this is a memory benchmark, we want to sample memory histograms at
-    # a high frequency.
-    options.AppendExtraBrowserArgs('--memory-metrics')
-
   def TabForPage(self, page, browser):
     return browser.tabs.New()