Reset the default value of touch event flag back to "Auto".

chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc

 // Copyright (c) 2013 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.
 
 #include "chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 240 matching lines @@
   }
   NOTREACHED();
   return UMA_LINUX_WINDOW_MANAGER_OTHER;
 }
 #endif
 
 void RecordTouchEventState() {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
   const std::string touch_enabled_switch =
-      command_line.HasSwitch(switches::kTouchEvents) ?
-      command_line.GetSwitchValueASCII(switches::kTouchEvents) :
-      switches::kTouchEventsEnabled;
+      command_line.HasSwitch(switches::kTouchEvents)
+          ? command_line.GetSwitchValueASCII(switches::kTouchEvents)
+          : switches::kTouchEventsAuto;
 
   UMATouchEventsState state;
   if (touch_enabled_switch.empty() ||
-      touch_enabled_switch == switches::kTouchEventsEnabled ||
-      touch_enabled_switch == switches::kTouchEventsAuto) {
+      touch_enabled_switch == switches::kTouchEventsEnabled) {
     state = UMA_TOUCH_EVENTS_ENABLED;
+  } else if (touch_enabled_switch == switches::kTouchEventsAuto) {
+    state = (ui::GetTouchScreensAvailability() ==
+             ui::TouchScreensAvailability::ENABLED)
+                ? UMA_TOUCH_EVENTS_AUTO_ENABLED
+                : UMA_TOUCH_EVENTS_AUTO_DISABLED;
   } else if (touch_enabled_switch == switches::kTouchEventsDisabled) {
     state = UMA_TOUCH_EVENTS_DISABLED;
   } else {
     NOTREACHED();
     return;
   }
 
   UMA_HISTOGRAM_ENUMERATION("Touchscreen.TouchEventsEnabled", state,
                             UMA_TOUCH_EVENTS_STATE_COUNT);
 }
@@ skipping 152 matching lines @@
   }
 }
 
 namespace chrome {
 
 void AddMetricsExtraParts(ChromeBrowserMainParts* main_parts) {
   main_parts->AddParts(new ChromeBrowserMainExtraPartsMetrics());
 }
 
 }  // namespace chrome