message: iModel in viewport is definitely defined
diff: @@ -269,7 +269,7 @@ export class Viewport {
  public get wantAntiAliasLines(): AntiAliasPref { return AntiAliasPref.Off; }
  public get wantAntiAliasText(): AntiAliasPref { return AntiAliasPref.Detect; }
  - public get iModel(): IModelConnection | undefined { return this.view.iModel; }
  + public get iModel(): IModelConnection { return this.view.iModel; }
  public isPointAdjustmentRequired(): boolean { return this.view.is3d(); }
  public isSnapAdjustmentRequired(): boolean { return IModelApp.toolAdmin.acsPlaneSnapLock && this.view.is3d(); }
  