<AWT Dev> [13] Review Request: 8223237 Replace use of string.equals("") with isEmpty() in java.desktop

[Sergey Bylokhov]

Hello.
Please review the fix for JDK 13.

Bug: https://bugs.openjdk.java.net/browse/JDK-8223237
Fix: http://cr.openjdk.java.net/~serb/8223237/webrev.00

This change is an equivalent of JDK-8214971[1] but for the java.desktop module.
  - The string.equals("") replaced by the string.isEmpty() in all cases
  - The "".equals(string) replaced by the string.isEmpty() when string is non-null
[1] https://bugs.openjdk.java.net/browse/JDK-8214971


In one case I dropped string.equals("") as unneeded:
http://cr.openjdk.java.net/~serb/8223237/webrev.00/src/java.desktop/share/classes/javax/swing/plaf/basic/BasicToolTipUI.java.udiff.html

-- 
Best regards, Sergey.