Shortcut for chaining css element finders gives TypeError after `findElement`

[rinatio]

Gettings an error

   Message:
     TypeError: Cannot call method 'css' of undefined

while chaining css element finders like

expect(element(by.css('html')).findElement(by.css('body')).$('div').isDisplayed()).toBe(true);

instead of

expect(element(by.css('html')).$('body').$('div').isDisplayed()).toBe(true);

[rinatio]

Replacing thisPtor.By with webdriver.By in element.$ and element.$$ methods helps to solve it

[juliemr]

Fixed the issue, but I think this is symptomatic of a larger confusion around WebElements and ElementFinders that I'd like to think about in #857