chromium/chrome/browser/resources/nearby_share/shared/nearby_device_icon.html

<style>
   /* TODO(b/279623883): Remove old colors when Jelly is launched. */
  :host {
    background-color: var(--nearby-device-icon-background-color, var(--cros-sys-primary_container,
                          var(--google-blue-50)));
    border-radius: 50%;
    display: flex;
  }

  #icon {
    height: var(--nearby-device-icon-size, 24px);
    margin: auto;
    width: var(--nearby-device-icon-size, 24px);
  }
</style>

<iron-icon id="icon" icon="[[getShareTargetIcon_(shareTarget)]]">
</iron-icon>