strict null checks: issueIpc.ts

fixes #61093

src/tsconfig.strictNullChecks.json

@@ -401,6 +401,7 @@
 		"./vs/platform/integrity/common/integrity.ts",
 		"./vs/platform/integrity/node/integrityServiceImpl.ts",
 		"./vs/platform/issue/common/issue.ts",
+		"./vs/platform/issue/node/issueIpc.ts",
 		"./vs/platform/jsonschemas/common/jsonContributionRegistry.ts",
 		"./vs/platform/keybinding/common/abstractKeybindingService.ts",
 		"./vs/platform/keybinding/common/keybinding.ts",

src/vs/platform/issue/node/issueIpc.ts

@@ -19,7 +19,7 @@ export class IssueChannel implements IIssueChannel {
 	constructor(private service: IIssueService) { }
 
 	listen<T>(event: string): Event<T> {
-		throw new Error('No event found');
+		throw new Error(`Event not found: ${event}`);
 	}
 
 	call(command: string, arg?: any): TPromise<any> {
@@ -29,7 +29,8 @@ export class IssueChannel implements IIssueChannel {
 			case 'openProcessExplorer':
 				return this.service.openProcessExplorer(arg);
 		}
-		return undefined;
+
+		throw new Error(`Call not found: ${command}`);
 	}
 }