src/vs/workbench/contrib/search/common/searchModel.ts/FileMatch/addContext
class FileMatch:	addContext(results: ITextSearchResult[] | undefined) {
		if (!results) { return; }

		results
			.filter((result => !resultIsMatch(result)) as ((a: any) => a is ITextSearchContext))
			.forEach(context => this._context.set(context.lineNumber, context.text));
	}