Add smoothScroll to scrollLines

src/browser/Viewport.ts

@@ -5,7 +5,7 @@
 
 import { Disposable } from 'common/Lifecycle';
 import { addDisposableDomListener } from 'browser/Lifecycle';
-import { IColorSet, IViewport, ReadonlyColorSet } from 'browser/Types';
+import { IColorSet, ISmoothScrollState, IViewport, ReadonlyColorSet } from 'browser/Types';
 import { ICharSizeService, ICoreBrowserService, IRenderService, IThemeService } from 'browser/services/Services';
 import { IBufferService, IOptionsService } from 'common/services/Services';
 import { IBuffer } from 'common/buffer/Types';
@@ -13,12 +13,6 @@ import { IRenderDimensions } from 'browser/renderer/shared/Types';
 
 const FALLBACK_SCROLL_BAR_WIDTH = 15;
 
-interface ISmoothScrollState {
-  startTime: number;
-  origin: number;
-  target: number;
-}
-
 /**
  * Represents the viewport of a terminal, the visible area within the larger buffer of output.
  * Logic for the virtual scroll bar is included in this object.