src/vs/platform/files/common/inMemoryFilesystemProvider.ts/InMemoryFileSystemProvider/delete
class InMemoryFileSystemProvider:	async delete(resource: URI, opts: IFileDeleteOptions): Promise<void> {
		let dirname = resources.dirname(resource);
		let basename = resources.basename(resource);
		let parent = this._lookupAsDirectory(dirname, false);
		if (parent.entries.has(basename)) {
			parent.entries.delete(basename);
			parent.mtime = Date.now();
			parent.size -= 1;
			this._fireSoon({ type: FileChangeType.UPDATED, resource: dirname }, { resource, type: FileChangeType.DELETED });
		}
	}