Turn gauge.js into a goog.module and ES6 class.
Turn gauge.js into a goog.module and ES6 class.

RELNOTES[INC]: Removed 'goog.ui.GaugeColoredRange' as a namespace.

PiperOrigin-RevId: 388472393
Change-Id: I675d065c7a18ac041918f7094d8ae69e61efc3d3

google/closure-library,google/closure-library,google/closure-library,google/closure-library,google/closure-library