message: WriteBarIcon: add aria-label & refactor
diff: position: relative;
  color: var(--writebar_icon);
  height: 52px;
  + width: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  /* iOS */
  .WriteBarIcon--ios {
  - width: 44px;
  color: var(--writebar_icon);
  }
  .WriteBarIcon--android,
  .WriteBarIcon--vkcom {
  - width: 44px;
  color: var(--icon_secondary);
  }
  