Fix @since for isIPhone() and isIPad(). (#14424, #14423)

Change-Id: I8b72b362134d564165a7037e0722c3ff28f59497

server/src/com/vaadin/server/WebBrowser.java

      * 
      * @return true if run on IPhone false if the user is not using IPhone or if
      *         no information on the browser is present
+     * @since 7.3.3
      */
     public boolean isIPhone() {
         return browserDetails.isIPhone();
      * 
      * @return true if run on IPad false if the user is not using IPad or if no
      *         information on the browser is present
+     * @since 7.3.3
      */
     public boolean isIPad() {
         return browserDetails.isIPad();

shared/src/com/vaadin/shared/VBrowserDetails.java

     /**
      * Tests if the browser is run on iPhone.
      * 
-     * @return
+     * @return true if run on iPhone, false otherwise
+     * @since 7.3.3
      */
     public boolean isIPhone() {
         return isIPhone;
     /**
      * Tests if the browser is run on iPad.
      * 
-     * @return
+     * @return true if run on iPad, false otherwise
+     * @since 7.3.3
      */
     public boolean isIPad() {
         return isIPad;