browser.wait(EC.textToBePresentInElement(element(by.binding('myvar')), "expected"), 5000, "Text is not something I've expected");

var EC = protractor.ExpectedConditions;

var anyTextToBePresentInElement = function(elementFinder) {
  var hasText = function() {
    return elementFinder.getText().then(function(actualText) {
      return actualText;
    });
  };
  return EC.and(EC.presenceOf(elementFinder), hasText);
};