Fix redundant specification warning

Change-Id: Icc485d1fab2e13ed1129c4cfc1c408cf73b87ad0
diff --git a/src/main/java/com/googlesource/gerrit/plugins/menuextender/client/OnEditEnabler.java b/src/main/java/com/googlesource/gerrit/plugins/menuextender/client/OnEditEnabler.java
index 96a8603..608c94f 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/menuextender/client/OnEditEnabler.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/menuextender/client/OnEditEnabler.java
@@ -46,7 +46,7 @@
    MouseUpHandler, ChangeHandler, ValueChangeHandler<Object> {
 
   private final FocusWidget widget;
-  private Map<TextBoxBase, String> strings = new HashMap<TextBoxBase, String>();
+  private Map<TextBoxBase, String> strings = new HashMap<>();
   private String originalValue;