Add parentNode check when removing JSONP request file

[FarSeeing]

Note: for support questions, please use one of these channels: https://github.com/angular/angular.js/blob/master/CONTRIBUTING.md#question. This repository's issues are reserved for feature requests and bug reports.

Do you want to request a feature or report a bug?
A bug.

What is the current behavior?
Currently the script element created for JSONP request is appended to document.body and removed on load or error callback:
httpBackend.js#L187

rawDocument.body.removeChild(script);

This will fail if the script was removed before the callback was fired.

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://plnkr.co or similar (template: http://plnkr.co/edit/tpl:yBpEi4).

What is the expected behavior?
Add a parentNode check instead of hardcoded document.body reference:

if (script.parentNode) script.parentNode.removeChild(script);

What is the motivation / use case for changing the behavior?

Which versions of Angular, and which browser / OS are affected by this issue? Did this work in previous versions of Angular? Please also test with the latest stable and snapshot (https://code.angularjs.org/snapshot/) versions.

Other information (e.g. stacktraces, related issues, suggestions how to fix)

[gkalpak]

I assume you ran into this issue. In order to better understand the issue, under what circumstances can this happen (the script being removed before the callback being called)?

[FarSeeing]

In my scenario we're scraping the page with PhantomJS and then remove (nearly) all the sripts from the page. This ends in document.body.removeChild(script) call to already removed/detached element.
I do understand it's a very rare condition but the check itself is not big either.

[gkalpak]

I am not arguing against the change. I just want to understand the usecase.
It is a reasonable change, so feel free to submit a pull request.