src/vs/workbench/api/common/extHostApiDeprecationService.ts/ExtHostApiDeprecationService/report
class ExtHostApiDeprecationService:	public report(apiId: string, extension: IExtensionDescription, migrationSuggestion: string): void {
		const key = this.getUsageKey(apiId, extension);
		if (this._reportedUsages.has(key)) {
			return;
		}
		this._reportedUsages.add(key);

		if (extension.isUnderDevelopment) {
			this._extHostLogService.warn(`[Deprecation Warning] '${apiId}' is deprecated. ${migrationSuggestion}`);
		}

		type DeprecationTelemetry = {
			extensionId: string;
			apiId: string;
		};
		type DeprecationTelemetryMeta = {
			extensionId: { classification: 'SystemMetaData', purpose: 'PerformanceAndHealth' };
			apiId: { classification: 'SystemMetaData', purpose: 'PerformanceAndHealth' };
		};
		this._telemetryShape.$publicLog2<DeprecationTelemetry, DeprecationTelemetryMeta>('extHostDeprecatedApiUsage', {
			extensionId: extension.identifier.value,
			apiId: apiId,
		});
	}