Linux: Remove --wm-user-time-ms command line argument

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index c9707ba406d2d7c74f16ce5e3dc00e5a1b32ef20..bef02a5e493305285178056b504128be4dbe1586 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -13481,12 +13481,6 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
-<histogram name="Event.Latency.X11EventSource.UpdateServerTime"
-    units="microseconds">

[jwd, 2016/08/31 14:13:00]

Please mark this as obsolete with a mm/yyyy of when, instead of removing it.

[Tom (Use chromium acct), 2016/08/31 17:27:47]

Done.

-  <owner>thomasanderson@chromium.org</owner>
-  <summary>Time to request a timestamp from the X server.</summary>
-</histogram>
-
 <histogram name="Event.MainThreadEventQueue.CoalescedCount" units="events">
   <owner>dtapuska@chromium.org</owner>
   <summary>
@@ -21315,6 +21309,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Linux.X11.ServerRTT" units="microseconds">
+  <owner>thomasanderson@chromium.org</owner>
+  <summary>
+    RTT between Chrome and the X11 server.  Tracked in X11EventSource by
+    measuring the latency to receive a property event after changing a property.
+  </summary>
+</histogram>
+
 <histogram name="LocalDiscovery.ClientRestartAttempts">
   <owner>noamsml@chromium.org</owner>
   <owner>vitalybuka@chromium.org</owner>