src/vs/editor/browser/widget/codeEditorWidget.ts/CodeEditorWidget/getTopForLineNumber
class CodeEditorWidget:	public getTopForLineNumber(lineNumber: number, includeViewZones: boolean = false): number {
		if (!this._modelData) {
			return -1;
		}
		return CodeEditorWidget._getVerticalOffsetForPosition(this._modelData, lineNumber, 1, includeViewZones);
	}