message: refactor: remove ternary operator because key is always true
diff: @@ -113,7 +113,7 @@ function genOnce (el: ASTElement, state: CodegenState): string {
  )
  return genElement(el, state)
  }
  - return `_o(${genElement(el, state)},${state.onceId++}${key ? `,${key}` : ``})`
  + return `_o(${genElement(el, state)},${state.onceId++},${key})`
  } else {
  return genStatic(el, state)
  }
  