8177678: Overstatement of universality of Era.getDisplayName() implementation

Reviewed-by: naoto

src/share/classes/java/time/chrono/Era.java

 /*
- * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -310,8 +310,8 @@ public interface Era extends TemporalAccessor, TemporalAdjuster {
      * The parameters control the style of the returned text and the locale.
      * <p>
      * If no textual mapping is found then the {@link #getValue() numeric value} is returned.
-     * <p>
-     * This default implementation is suitable for all implementations.
+     *
+     * @apiNote This default implementation is suitable for most implementations.
      *
      * @param style  the style of the text required, not null
      * @param locale  the locale to use, not null

src/share/classes/java/time/chrono/JapaneseEra.java

 /*
- * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -239,19 +239,10 @@ public final class JapaneseEra
     }
 
     /**
-     * Gets the textual representation of this era.
-     * <p>
-     * This returns the textual name used to identify the era,
-     * suitable for presentation to the user.
-     * The parameters control the style of the returned text and the locale.
-     * <p>
-     * If no textual mapping is found then the {@link #getValue() numeric value}
-     * is returned.
+     * {@inheritDoc}
      *
-     * @param style  the style of the text required, not null
-     * @param locale  the locale to use, not null
-     * @return the text value of the era, not null
-     * @since 9
+     * @param style {@inheritDoc}
+     * @param locale {@inheritDoc}
      */
     @Override
     public String getDisplayName(TextStyle style, Locale locale) {