<Sound Dev> [9] Review Request: 8058115 Some of MidiDeviceProviders do not follow the specification

[Sergey Bylokhov]

Hello,
Please review the fix for jdk 9.
Changes description:
  - SoftProvider.java/ RealTimeSequencerProvider.java: getDevice now 
does not return null for unsupported devices + small cleanup.
  - MidiDeviceProvider.java: isDeviceSupported now does not throw 
unspecified NPE in case of null parameter.
  - AbstractMidiDeviceProvider.java: getDevice now does not throw 
unspecified NPE in case of null parameter.
  - MidiSystem.java: small cleanup of a related to MidiDevice methods.
In some places the String.format now used instead of string 
concatenation in non performance critical code to make class file smaller.

Bug: https://bugs.openjdk.java.net/browse/JDK-8058115
Webrev can be found at: http://cr.openjdk.java.net/~serb/8058115/webrev.00

-- 
Best regards, Sergey.