Adds a first-run balloon to the Windows notification center.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 459210e56fcfc31d731ce17a304c491def983d78..2e66ac9253a904d74aee456879cf087585a52d01 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -2156,6 +2156,11 @@ const char kDisableCloudPolicyOnSignin[] =
 // Indicates that factory reset was requested from options page.
 const char kFactoryResetRequested[] = "FactoryResetRequested";
 
+// Boolean recording whether we have showed a balloon that calls out the message
+// center for desktop notifications.
+const char kMessageCenterShowedFirstRunBalloon[] =
+    "message_center.showed_first_run_balloon";
+
 // *************** SERVICE PREFS ***************
 // These are attached to the service process.