- Made console stream fields final for ProcessConsole and InputReadJob
- closeStreams() should first set fStreamsClosed to true before closing
the stream, to give the InputReadJob a chance to exist without error
- InputReadJob should consider that stream could be closed via
canceling()
- don't log IO errors from InputReadJob if we know that stream is closed

Fixes https://github.com/eclipse-platform/eclipse.platform/issues/1033