Remove obsolete --running-performance-benchmark flag.

Flag was added in http://crrev.com/433623002/ but does not
appear to be in use any longer (and appears to have only
been used for Clank-specific purposes).

CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.perf:android_s5_perf_cq;master.tryserver.chromium.perf:linux_perf_cq;master.tryserver.chromium.perf:mac_retina_perf_cq

Review-Url: https://codereview.chromium.org/2370793004
Cr-Commit-Position: refs/heads/master@{#421207}

content/public/android/java/src/org/chromium/content/common/ContentSwitches.java

@@ -27,10 +27,6 @@ public abstract class ContentSwitches {
     // Change the url of the JavaScript that gets injected when accessibility mode is enabled.
     public static final String ACCESSIBILITY_JAVASCRIPT_URL = "accessibility-js-url";
 
-    // Indicates Chrome is running for performance benchmark.
-    public static final String RUNNING_PERFORMANCE_BENCHMARK =
-            "running-performance-benchmark";
-
     // Sets the ISO country code that will be used for phone number detection.
     public static final String NETWORK_COUNTRY_ISO = "network-country-iso";
 

tools/perf/measurements/smoothness.py

@@ -39,7 +39,6 @@ class Smoothness(legacy_page_test.LegacyPageTest):
   def CustomizeBrowserOptions(cls, options):
     options.AppendExtraBrowserArgs('--enable-gpu-benchmarking')
     options.AppendExtraBrowserArgs('--touch-events=enabled')
-    options.AppendExtraBrowserArgs('--running-performance-benchmark')
 
   def WillNavigateToPage(self, page, tab):
     # FIXME: Remove webkit.console when blink.console lands in chromium and