performance property Null safety

Performance performance

@SupportedBrowser(SupportedBrowser.CHROME), @SupportedBrowser(SupportedBrowser.FIREFOX), @SupportedBrowser(SupportedBrowser.IE)

Timing and navigation data for this window.

Other resources

Measuring page load speed with navigation timeing from HTML5Rocks.
Navigation timing specification from W3C.

Implementation

@SupportedBrowser(SupportedBrowser.CHROME)
@SupportedBrowser(SupportedBrowser.FIREFOX)
@SupportedBrowser(SupportedBrowser.IE)
Performance get performance native;