fix($sniffer) & fix(ng-input): add check for older webkit browsers and extra milliseconds for iOS7

[WardMe]

Request Type: bug

How to reproduce:

• $sniffer: Create a multipage app with redirects in angular and test it in Android or Safari 5 or lower, the app will end up in an endless loop and eventually crash the browser.
• ng-input: Create a form with validation and try to submit on an iOS7 device, the last character never gets sent, so the form always returns invalid.

Component(s): misc core

Impact: medium

Complexity: small

This issue is related to: #6733

Detailed Description:

We created a responsive web app in angular, but ran into two issues:

• older webkit engines (< 534) have problem with pushState, these are used in Safari 5 and lower and the Android default browser (not Chrome)
• iOS7 the change event is fired before the value is updated

[mary-poppins]

Thanks for the PR! Please check the items below to help us merge this faster. See the contributing docs for more information.

• Uses the issue template (#6890)

If you need to make changes to your pull request, you can update the commit with git commit --amend.
Then, update the pull request with git push -f.

Thanks again for your help!

[caitp]

I believe these are dupes of other PRs that I recall seeing, but please send these as separate pull requests

[IgorMinar]

I wonder if the infinite loop is due to some encoding issue (#5019).

the second commit doesn't look right. as far as I can tell iOS7 has proper input event support (see) which means that we don't rely on the keydown event

[IgorMinar]

@tbosch do you know about input event support in iOS7?

[caitp]

this has become bitrotten, and I think it would be good to create a demonstration of the issue before a change is merged... @WardMe could I ask you to please submit an updated pull request and provide a reproduction for the issue that you're fixing? It would be much appreciated.