Remove DocumentMode usage histogram.

chrome/browser/metrics/android_metrics_provider.cc

 // Copyright 2014 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/android_metrics_provider.h"
 
 #include "base/metrics/histogram_macros.h"
 #include "base/sys_info.h"
 #include "base/values.h"
 #include "chrome/browser/android/feature_utilities.h"
@@ skipping 29 matching lines @@
 }
 
 void AndroidMetricsProvider::ProvideStabilityMetrics(
     metrics::SystemProfileProto* system_profile_proto) {
   ConvertStabilityPrefsToHistograms();
 }
 
 void AndroidMetricsProvider::ProvideGeneralMetrics(
     metrics::ChromeUserMetricsExtension* uma_proto) {
   UMA_HISTOGRAM_ENUMERATION(
-      "DocumentActivity.Enabled",
-      chrome::android::GetDocumentModeValue(),
-      chrome::android::RUNNING_MODE_MAX);
-  UMA_HISTOGRAM_ENUMERATION(
       "CustomTabs.Visible",
       chrome::android::GetCustomTabsVisibleValue(),
       chrome::android::CUSTOM_TABS_VISIBILITY_MAX);
   UMA_HISTOGRAM_BOOLEAN(
       "MemoryAndroid.LowRamDevice",
       base::SysInfo::IsLowEndDevice());
   UMA_HISTOGRAM_BOOLEAN(
       "Android.MultiWindowMode.Active",
       chrome::android::GetIsInMultiWindowModeValue());
 }
@@ skipping 93 matching lines @@
     for (int count = 0; count < crash_count; ++count) {
       UMA_STABILITY_HISTOGRAM_ENUMERATION("Chrome.Android.Activity.CrashCounts",
                                           activity_type,
                                           ActivityTypeIds::ACTIVITY_MAX_VALUE);
     }
   }
 
   launch_counts->Clear();
   crash_counts->Clear();
 }