message: Add aria-labels to ActionButtons
diff: @@ -77,6 +77,7 @@ export default React.createClass({
  onClick={this._onClick}
  onMouseEnter={this._onMouseEnter}
  onMouseLeave={this._onMouseLeave}
  + aria-label={this.props.label}
  >
  <TintableSvg src={this.props.iconPath} width={this.props.size} height={this.props.size} />
  { tooltip }
  