Try these stylings:
input[type="search"]::-webkit-search-decoration,
input[type="search"]::-webkit-search-cancel-button,
input[type="search"]::-webkit-search-results-button,
input[type="search"]::-webkit-search-results-decoration {
-webkit-appearance:none;
}
Source: http://css-tricks.com/webkit-html5-search-inputs/#comment-82432