src/vs/editor/common/viewModel/overviewZoneManager.ts/OverviewZoneManager/setDOMHeight
class OverviewZoneManager:	public setDOMHeight(height: number): boolean {
		if (this._domHeight === height) {
			return false;
		}
		this._domHeight = height;
		this._colorZonesInvalid = true;
		return true;
	}