src/vs/workbench/api/common/extHostExtensionService.ts/AbstractExtHostExtensionService/getExtension
class AbstractExtHostExtensionService:	public async getExtension(extensionId: string): Promise<IExtensionDescription | undefined> {
		const ext = await this._mainThreadExtensionsProxy.$getExtension(extensionId);
		return ext && {
			...ext,
			identifier: new ExtensionIdentifier(ext.identifier.value),
			extensionLocation: URI.revive(ext.extensionLocation),
		};
	}