src/vs/workbench/api/common/extHostSearch.ts/ExtHostSearch/$provideTextSearchResults
class ExtHostSearch:	$provideTextSearchResults(handle: number, session: number, rawQuery: IRawTextQuery, token: vscode.CancellationToken): Promise<ISearchCompleteStats> {
		const provider = this._textSearchProvider.get(handle);
		if (!provider || !provider.provideTextSearchResults) {
			throw new Error(`Unknown provider ${handle}`);
		}

		const query = reviveQuery(rawQuery);
		const engine = this.createTextSearchManager(query, provider);
		return engine.search(progress => this._proxy.$handleTextMatch(handle, session, progress), token);
	}