onProgress property Null safety

Stream<ProgressEvent> onProgress
@SupportedBrowser(SupportedBrowser.CHROME)@SupportedBrowser(SupportedBrowser.FIREFOX)@SupportedBrowser(SupportedBrowser.IE, '10')@SupportedBrowser(SupportedBrowser.SAFARI)

Stream of progress events handled by this HttpRequestEventTarget.

Implementation

@SupportedBrowser(SupportedBrowser.CHROME)
@SupportedBrowser(SupportedBrowser.FIREFOX)
@SupportedBrowser(SupportedBrowser.IE, '10')
@SupportedBrowser(SupportedBrowser.SAFARI)
Stream<ProgressEvent> get onProgress => progressEvent.forTarget(this);