Update account and sync management UX

chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java

Index: chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java
index dc93b417f958ee1291d8652110db54de4d7d212e..a735c761618314dfb929ed50a496b1589aa27f95 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountManagementScreenHelper.java
@@ -23,6 +23,15 @@ public class AccountManagementScreenHelper {
      * Enum for the Gaia service types, must match GAIAServiceType in
      * signin_header_helper.h
      */
+    /**
+     * The signin::GAIAServiceType value used in openAccountManagementScreen when the dialog
+     * hasn't been triggered from the content area.
+     */
+    public static final int GAIA_SERVICE_TYPE_NONE = 0;
+    /**
+     * The signin::GAIAServiceType value used when openAndroidAccountCreationScreen is triggered by
+     * the GAIA service to create a new account
+     */
     public static final int GAIA_SERVICE_TYPE_SIGNUP = 5;
 
     private static final String EXTRA_ACCOUNT_TYPES = "account_types";