Add metrics to help measure effects of installing default apps in a profile.

chrome/browser/extensions/extension_service.cc

Index: chrome/browser/extensions/extension_service.cc
===================================================================
--- chrome/browser/extensions/extension_service.cc	(revision 103881)
+++ chrome/browser/extensions/extension_service.cc	(working copy)
@@ -11,6 +11,7 @@
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/logging.h"
+#include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/stl_util.h"
@@ -27,6 +28,7 @@
 #include "chrome/browser/chrome_plugin_service_filter.h"
 #include "chrome/browser/extensions/apps_promo.h"
 #include "chrome/browser/extensions/crx_installer.h"
+#include "chrome/browser/extensions/default_apps_trial.h"
 #include "chrome/browser/extensions/extension_accessibility_api.h"
 #include "chrome/browser/extensions/extension_bookmarks_module.h"
 #include "chrome/browser/extensions/extension_browser_event_router.h"
@@ -963,6 +965,14 @@
   UserMetrics::RecordAction(
       UserMetricsAction("Extensions.ExtensionUninstalled"));
 
+  static bool default_apps_trial_exists =
+      base::FieldTrialList::TrialExists(kDefaultAppsTrial_Name);
+  if (default_apps_trial_exists) {
+    UserMetrics::RecordComputedAction(
+        base::FieldTrial::MakeName("Extensions.ExtensionUninstalled",
+                                   kDefaultAppsTrial_Name));
+  }
+
   return true;
 }