Mark htmlEscapeAllowEntities as @IsSafeHtml

Change-Id: I74fd6411582907b58d955631c4cb0f53a2cca9b1

user/src/com/google/gwt/safehtml/shared/SafeHtmlUtils.java

diff --git a/user/src/com/google/gwt/safehtml/shared/SafeHtmlUtils.java b/user/src/com/google/gwt/safehtml/shared/SafeHtmlUtils.java
index 7e10bf4..5ac4e24 100644
--- a/user/src/com/google/gwt/safehtml/shared/SafeHtmlUtils.java
+++ b/user/src/com/google/gwt/safehtml/shared/SafeHtmlUtils.java
@@ -16,6 +16,8 @@
 package com.google.gwt.safehtml.shared;
 
 import com.google.gwt.regexp.shared.RegExp;
+import com.google.gwt.safehtml.shared.annotations.IsSafeHtml;
+import com.google.gwt.safehtml.shared.annotations.SuppressIsSafeHtmlCastCheck;
 
 /**
  * Utility class containing static methods for escaping and sanitizing strings.
@@ -190,6 +192,8 @@
    *         exception that ampersand characters are not double-escaped if they
    *         form the start of an HTML Entity Reference
    */
+  @IsSafeHtml
+  @SuppressIsSafeHtmlCastCheck
   public static String htmlEscapeAllowEntities(String text) {
     StringBuilder escaped = new StringBuilder();