Hide TextDirectionHeuristics

Bug 6435363

Change-Id: I9ba0a3c057af67e2876e64fd8c18adbb8f4d0860
diff --git a/core/java/android/text/TextDirectionHeuristics.java b/core/java/android/text/TextDirectionHeuristics.java
index 6ca6161..bbaa173 100644
--- a/core/java/android/text/TextDirectionHeuristics.java
+++ b/core/java/android/text/TextDirectionHeuristics.java
@@ -22,6 +22,8 @@
 
 /**
  * Some objects that implement TextDirectionHeuristic.
+ *
+ * @hide
  */
 public class TextDirectionHeuristics {