RelatedInformationService shouldn't throw on timeout (microsoft#196643)

It should just return no results.

Fixes microsoft/vscode-copilot#2237

Author: TylerLeonhardt

src/vs/workbench/services/aiRelatedInformation/common/aiRelatedInformationService.ts

@@ -83,7 +83,7 @@ export class AiRelatedInformationService implements IAiRelatedInformationService
 				AiRelatedInformationService.DEFAULT_TIMEOUT,
 				() => {
 					cancellablePromises.forEach(p => p.cancel());
-					throw new Error('Related information provider timed out');
+					this.logService.warn('[AiRelatedInformationService]: Related information provider timed out');
 				}
 			);
 			if (!results) {

src/vs/workbench/services/aiRelatedInformation/test/common/aiRelatedInformationService.test.ts

@@ -4,6 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as assert from 'assert';
+import * as sinon from 'sinon';
 import { AiRelatedInformationService } from 'vs/workbench/services/aiRelatedInformation/common/aiRelatedInformationService';
 import { NullLogService } from 'vs/platform/log/common/log';
 import { CommandInformationResult, IAiRelatedInformationProvider, RelatedInformationType, SettingInformationResult } from 'vs/workbench/services/aiRelatedInformation/common/aiRelatedInformation';
@@ -66,4 +67,28 @@ suite('AiRelatedInformationService', () => {
 		assert.strictEqual((result[0] as CommandInformationResult).command, command);
 		assert.strictEqual((result[1] as SettingInformationResult).setting, setting);
 	});
+
+	test('should return empty array on timeout', async () => {
+		const clock = sinon.useFakeTimers({
+			shouldAdvanceTime: true,
+		});
+		const provider: IAiRelatedInformationProvider = {
+			provideAiRelatedInformation: () => new Promise((resolve) => {
+				setTimeout(() => {
+					resolve([{ type: RelatedInformationType.CommandInformation, command: 'command', weight: 1 }]);
+				}, AiRelatedInformationService.DEFAULT_TIMEOUT + 100);
+			})
+		};
+
+		service.registerAiRelatedInformationProvider(RelatedInformationType.CommandInformation, provider);
+
+		try {
+			const promise = service.getRelatedInformation('query', [RelatedInformationType.CommandInformation], CancellationToken.None);
+			clock.tick(AiRelatedInformationService.DEFAULT_TIMEOUT + 200);
+			const result = await promise;
+			assert.strictEqual(result.length, 0);
+		} finally {
+			clock.restore();
+		}
+	});
 });