fix animation transform: rotate(360deg)

[suyulin]

fixed animation transform: rotate(360deg) not work.

@keyframes van-rotate {
  from {
    transform: rotate(0deg);
  }

  to {
    transform: rotate(360deg);
  }
}

[andycall]

Test specs also needed

@suyulin

[suyulin]

Don't know how to write the test,
before:

@keyframes van-rotate {
  from {
    transform: rotate(0deg);
  }

  to {
    transform: rotate(360deg);
  }
}

no animation action
after:
element can spin

[andycall]

@suyulin done