code: private String requestAccountName(DropboxAPI<AndroidAuthSession> dropboxApi) {
          String accountName = null;
          if (dropboxApi != null) {
              try {
                  accountName = dropboxApi.accountInfo().displayName;
              } catch (DropboxException e) {
                  // Do nothing.
              }
          }
          return accountName;
      }
docs: Requests the linked account name.
  
  @param dropboxApi the {@link DropboxAPI}.
  @return the account name; or null if not linked.