message: test(DropdownMenu): fix snapshot
diff: @@ -28,7 +28,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -36,7 +36,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -70,7 +70,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -78,7 +78,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -112,7 +112,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -120,7 +120,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -154,7 +154,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="bottom: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--up"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -162,7 +162,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="bottom: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--up"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -196,7 +196,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  @@ -204,7 +204,7 @@ exports[`should render demo and match snapshot 1`] = `
  <div style="top: 0px; display: none;"
  class="van-dropdown-item van-dropdown-item--down"
  >
  - <transition-stub style="position: absolute;">
  + <transition-stub>
  </transition-stub>
  <transition-stub>
  </transition-stub>
  