Fixing Javadoc warnings

Author: Jaroslav Tulach

truffle/com.oracle.truffle.api.object/src/com/oracle/truffle/api/object/Layout.java

@@ -86,7 +86,7 @@ public static Layout createLayout() {
      * @param objectType that describes the object instance with this shape.
      * @param sharedData for language-specific use
      * @param id for language-specific use
-     * @return
+     * @return new instance of a shape
      */
     public abstract Shape createShape(ObjectType objectType, Object sharedData, int id);
 

truffle/com.oracle.truffle.api.object/src/com/oracle/truffle/api/object/Property.java

@@ -35,7 +35,10 @@ protected Property() {
     /**
      * Create a new property.
      *
-     * @param flags, for language-specific use
+     * @param key the key of the property
+     * @param location location of the property
+     * @param flags for language-specific use
+     * @return new instance of the property
      */
     public static Property create(Object key, Location location, int flags) {
         return Layout.getFactory().createProperty(key, location, flags);