React 0.14.7: `<option value="">empty</option>` emits empty string on change
http://jsbin.com/pisita/10/edit?html,js,console,output
React 15.0.0-rc.1`<option value="">empty</option>` emits string with value "empty" on change
http://jsbin.com/bemaze/12/edit?html,js,console,output
This is because React 15.0.0-rc.1 cuts off `value=""` from option tag

kind: 0,
    label: 0,
    lang: 0,
    list: 0,
    loop: HAS_BOOLEAN_VALUE,
    low: 0,
    manifest: 0,
    marginHeight: 0,
    marginWidth: 0,
    max: 0,
    maxLength: 0,
    media: 0,
    mediaGroup: 0,
    method: 0,
    min: 0,
    minLength: 0,
    
    
    multiple: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
    muted: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
    name: 0,
    nonce: 0,
    noValidate: HAS_BOOLEAN_VALUE,
    open: HAS_BOOLEAN_VALUE,
    optimum: 0,
    pattern: 0,
    placeholder: 0,
    poster: 0,
    preload: 0,
    profile: 0,